Pentagonal prism surface area calculator

Solution: As we know, Total Surface Area ( TSA) = 5 b h + 1 2 5 ( 5 + 2 5) b 2 , here b = 11 cm, h = 6 cm. ∴ TSA = 5 × 11 × 7 + 1 2 5 ( 5 + 2 5) × 11 2. = 801.35 cm 2. What is the surface area of a pentagonal …

Pentagonal prism surface area calculator. Jan 18, 2024 · Assume it's equal to 80 in, type this value into the first box of the triangular prism calculator. Choose the option with your parameters given. For example, given three sides of our base. Enter base sides. Our tent has a = 60 in, b = 50 in and c = 50 in. Triangular prism surface area and volume appear in no time. It's 96,000 cu in (55.56 cu ft ...

From the net, you can see that that the surface area of the entire prism equals the sum of the figures that make up the net: Total surface area = area A + area B + area C + area D + area E + area F. Using the formula for the area of a rectangle, you can see that the area of rectangle A is:. A = l · w A = 10 · 5 = 50 square units. Similarly, the …

Cone Surface Area Calculator. Calculate cone surface area step by step. What I want to Find. Surface Area Given Lateral Surface Surface Area Given Radius Lateral Surface Given Slant Height Lateral Surface Given Height Lateral Surface Given Surface Area.The oceans take up most of the surface area of our planet and remain mostly unexplored. But how many oceans are there? Advertisement Planet Earth, when viewed from space, has been ...The total surface area of pentagonal prism = 5ab + 5bh = 5ab + LSA = (5 × 15 × 20) + 1500 = 1500 + 1500 = 3000 sq units. Therefore, the lateral surface area of the pentagonal prism is 1500 sq units and the total …Surface Area. The surface area of a right prism is the total space occupied by its outermost faces. It is expressed in square units such as cm 2, m 2, mm 2, in 2, or yd 2. Surface area of a right prism is of 2 types. Lateral Surface Area. The lateral surface area (LSA) of a right prism is only the sum of the surface area of all its faces except ...The total surface area of a pentagonal prism = 5as + 5sh square units = 5 (6 × 10) + 5 (10 × 13) = 5(60) + 5(150) = 300 + 750 = 1050 sq. in. Therefore, the total surface area of a pentagonal prism is 1050 sq. inches. Example 4: Find the lateral surface area of the pentagonal prism whose apothem length is 4 cm, base length is 7 …28 Mar 2018 ... Rachel Briscoe · Lateral Area and Surface Area of Cones, Pyramids, Cylinders & Prisms · How to Find the Volume of a Triangular Prism | Math with&n...About this page: Hexagonal Prism Calculator The hexagonal prism calculator finds the volume of a regular hexagonal prism with two hexagonal bases and six rectangular faces, using length of the side of the prism l and its height h.In addition, the page computes surface to volume ratio, the total surface area, the lateral surface area, and surface …Therefore the volume of the pentagonal prism is 3750cm 3. Surface area of pentagonal prism =5*a*b+5*b*h square units =5(5*20)+5(20*15) =5*100+5*300 =500+1500 =2000cm 2. Therefore the surface area of a pentagonal prism 2000cm 2. Example:2. Calculate the surface area and volume of the pentagonal prism with apothem length of 3cm, base length 9cm ...

Solution: As we know, Total Surface Area ( TSA) = 5 b h + 1 2 5 ( 5 + 2 5) b 2 , here b = 11 cm, h = 6 cm. ∴ TSA = 5 × 11 × 7 + 1 2 5 ( 5 + 2 5) × 11 2. = 801.35 cm 2. What is the surface area of a pentagonal …6 days ago · The pentagonal prism is a prism having two pentagonal bases and five rectangular sides. It is a heptahedron. The regular right pentagonal prism is uniform polyhedron U_(76). Its dual polyhedron is the pentagonal dipyramid. A (possibly nonregular) pentagonal prism is the convex hull of the pentagrammic antiprism, pentagrammic prism, and pentagrammic crossed antiprism. The dual polyhedron of the ... Find the total surface area of a hexagonal prism with a base edge of 4 cm and a height of 7.5 cm. Solution: Here we will use an alternative formula. Total Surface Area ( TSA) = 6 b h + 3 3 × b 2, here b = 4 cm, h = 7.5 cm. ∴ T S A = 6 × 4 × 7.5 + 3 3 × 4 2. ≈ 263 cm 2. Finding the surface area of a hexagonal prism when BASE PERIMETER ...6 Mar 2023 ... I have no idea wtf or how tf to calculate the volume of a pentagon-based prism. pls help '_'. Question: The triangular prism has a base area of ...

Practice Problems on Surface Area of Prisms. Give these problems a shot for some practice: Find the surface area of a triangular prism with a base area of 10 square units, a base perimeter of 12 units, and a height of 5 units. Calculate the surface area of a rectangular prism with a length of 6 units, a width of 4 units, and a height of 3 units.Volume and surface area of cylinders. Applying volume of solids. Volume of composite figures ... It is frustrating to get sent back to zero when you use your calculator correctly but you should just use one standard calculation of 3.14. ... Any prism volume is V = BH where B is area of base and H is height of prism, so find area of the base by ...... calculate either surface area or volume, that information is here also. A good example of a pentagonal prism for reference purposes is the U.S. Pentagon ...10 Apr 2024 ... Two pentagonal bases. 2. Five rectangular lateral faces. Let's calculate each part: Area of each pentagonal base: The area of a regular pentagon ...Pentagon Area Calculator: Looking for a free and handy calculator to check out the area of a pentagon?No need to search for more tools because this online Pentagon Area Calculator is the best out of all. You can easily find out the area by giving the length of the side of a pentagon in the input field of our Pentagon Area Calculator.

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Pentagonal Prism Surface Area Calculator. You can calculate the lateral surface area and the total surface area of the Pentagonal prism by inputting the required value for the calculation. The variables in the calculator include. Base Length (a) The length of the side of the Pentagonal base. Height (h) The height of the prism. 4 days ago · The surface area of a rectangular prism calculator gives us the answer: A = 2 × l × w + 2 × l × h + 2 × w × h = 2 × 8 ft × 6 ft + 2 × 8 ft × 5 ft + 2 × 6 ft × 5 ft = 236 ft². But that is the surface area of the entire prism, and we don't want to tile it all around. After all, if we tile the top, it would be pretty difficult to get ... Surface Area of a Prism. Surface Area = 2 × Base Area. + Base Perimeter × Length. Example: What is the surface area of a prism where the base area is 25 m 2, the base perimeter is 24 m, and the length is 12 m: Surface Area = 2 × Base Area + Base Perimeter × Length. = 2 × 25 m2 + 24 m × 12 m. = 50 m2 + 288 m2.The Lateral Surface Area of Pentagonal Prism formula is defined as the quantity of plane enclosed by all the lateral surfaces (that is, top and bottom faces are excluded) of the Pentagonal Prism is calculated using Lateral Surface Area of Pentagonal Prism = 5*Base Edge Length of Pentagonal Prism*Height of Pentagonal Prism. To calculate Lateral ...Surface area of a triangular prism. The surface area formula for a triangular prism is 2 * (height x base / 2) + length x width 1 + length x width 2 + length x base, as seen in the figure below: A triangular prism is a stack of triangles, so the usually triangle solving rules apply when calculating the area of the bases.

Use the simple geometry calculator to calculate the lateral surface area of a right prism online. Geometry Prisms - Definitions. A Prism is a polyhedron with two congruent polygonal faces that lie in parallel planes.; The Bases are the parallel polygonal faces.; The Lateral Faces are the faces that are not bases.; The Lateral Edges are the …To find out the surface area of a prism, we need to calculate the areas of all of its faces and then add all the areas obtained. The lateral surface area of a prism is the area occupied by the faces of a prism, excluding the identical faces (bases of a prism) facing each other. ... The total surface area of the pentagonal prism = 5ab + 5bh. ⇒ ...... Prism can be defined as a flat side of a 3-dimensional object. There are seven Prism faces. 2. Calculate the Surface Area and the Volume of the Pentagonal Prism ...The surface area of a pentagonal prism can be calculated using the formula: A = 2 × B + P × h, where B is the area of the base, P is the base’s perimeter, …Triangular Pyramid Surface Area Calculator. The surface area of triangular pyramid calculator handles all pyramid related calculations like a pro. It doesn’t matter if you want to find the surface area, volume, base area, base width, or base length. ... Pentagonal. Area of Base : [(5/2)as] Surface Area of Pyramid : [(5/2)as + (5/2)sl] Volume ...A pentagonal prism is a type of prism that uses a pentagon for a base. It's volume and total surface area can be calculated using the tool provided. Equation form: Surface Area (SA) =. √ (25 + 10 * √5) * a². + 5 * l * h. 2. Volume (V) =. √ (25 + 10 * √5) * a² * h. Pentagonal Pyramid Calculation. Calculator and formulas for calculating a regular pentagonal based pyramid ... Lateral Surface A L: Surface area S: Perimeter P: Volume V: Percent means out of 100, so 100 percent is a way to express the full amount of something. Viewing data in the form of percents helps you quickly evaluate what portion of a whole y...Here's the most basic formula for triangular prism surface that we can use: Area = Length × (a + b + c) + (2 × Base area) or. Area = Length × Base perimeter + (2 × …Surface Area Calculation. Calculate the surface area of a right regular pentagonal prism with a side length of 4 cm and height 12 cm. Solution. First, calculate the area of the base, B, and the perimeter of the base: B = 5/4 × 4² × cot(π/5) B = 19.7 cm². P = 5 × 4 = 20 cm. The surface area A is given by: A = 2 × B + P × h

Oblique Prism Calculator. Calculations at an oblique prism. Different to a right prism, the sides are not perpendicular to the bases (angle of slope ≠ 90°). Cavalieri's principle says, that the volume of the oblique prism is similar to that of the right prism with equal base and height. The surface area can be calculated as 2 * base area ...

Formula for Surface Area: The surface area of a regular pentagonal pyramid can be calculated using the following formula: A = (5/4) × l² × √(25 + 10 × √5) × h². Formula for Volume: The volume of a regular pentagonal pyramid can be calculated using the following formula: V = (5/12) × l² × h × √(5 – 2 × √5) The pentagonal prism, as the name suggests, has a pentagon as its base. Understanding the surface area of a pentagonal prism is essential for various real-world applications, such as calculating the amount of material needed to create a container or constructing architectural structures. How to find the total surface area of a pentagonal prism WITH or WITHOUT knowing the apothem or slant height. Either way, I'll show you. If you don't underst... To use this online calculator for Volume of Pentagonal Prism, enter Base Edge Length of Pentagonal Prism (le (Base)) & Height of Pentagonal Prism (h) and hit the calculate button. Here is how the Volume of Pentagonal Prism calculation can be explained with given input values -> 2580.716 = sqrt (5* (5+ (2*sqrt (5))))/4*10^2*15. In Texas, local entities set the rate for property taxes each fiscal year. If they raise the tax rate up past a level known as the rollback rate, taxpayers in the area can petition...4 days ago · SA = a2 + 2×a×l. 🔎 Proof: The surface area of a square pyramid is the sum of the areas of its square base and four triangular faces: SA = BA + (4 × FA) The area of a triangle is half of the product of its base length ( a) and height ( l ): FA = a×l/2. We used cost of living data and the 50/30/20 rule budget to calculate how much it takes to live comfortably in the largest 25 metro areas in the U.S. Calculators Helpful Guides Com...Surface Area Calculations for a regular right pentagonal prism.We generate a 3D view, then explode it into a net.Following our McDougal-Littell textbook, we ...Practice Problems on Surface Area of Prisms. Give these problems a shot for some practice: Find the surface area of a triangular prism with a base area of 10 square units, a base perimeter of 12 units, and a height of 5 units. Calculate the surface area of a rectangular prism with a length of 6 units, a width of 4 units, and a height of 3 units.

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The convenient to use surface area calculator will calculate this for you. FAQ How to find volume? The volume formula depends on the shape of the object. One of the most popular shapes is a rectangular prism, also known as a box, where you can simply multiply length times width times height to find its volume. Another common … The pentagonal prism, as the name suggests, has a pentagon as its base. Understanding the surface area of a pentagonal prism is essential for various real-world applications, such as calculating the amount of material needed to create a container or constructing architectural structures. You can calculate the area of a circle with the following formula: A_ {\text {base}}=\pi\cdot r^2 Abase = π ⋅ r2. where: r r — Radius of a circle. Later, we will add this base area equation to the equation we will derive next for the lateral area of a right cone. A cone folded flat forms a sector of a larger circle.In Texas, local entities set the rate for property taxes each fiscal year. If they raise the tax rate up past a level known as the rollback rate, taxpayers in the area can petition...First work out the area of the triangle. Multiply the base by the height and divide by two, (5 × 4)/2 = 10. The area of the triangular cross-section is 10 mm². Image caption, Next multiply the ...About Pentagonal Pyramid (Johnson solids) Calculator tool. Remember this tool should be used only to calculate area, perimeter or volume of a figure. The results we provide are accurate, but rounded to the 12th decimal place. It accepts scientific notation and converts immediately. pentagonal pyramid (Johnson solids) properties, calculate ...We used cost of living data and the 50/30/20 rule budget to calculate how much it takes to live comfortably in the largest 25 metro areas in the U.S. Calculators Helpful Guides Com...area = a² × √(25 + 10√5) / 4, where a is a side of a regular pentagon. Also, you can find the area having the circumscribed circle radius: area = 5R² × √[(5 + √5)/2] / 4, where R is the circumcircle radius. Perimeter P of a regular pentagon is equal to the side length multiplied by the number of vertices. A pentagon is a five-sided ... Pentagonal Pyramid Calculation. Calculator and formulas for calculating a regular pentagonal based pyramid ... Lateral Surface A L: Surface area S: Perimeter P: Volume V: The steps to determine the surface area of the prism are: Step 1: Note down the given dimensions of the prism. Step 2: Substitute the dimensions in the surface area of prism formula (2 × Base Area) + (Base perimeter × height). Step 3: The value of the surface area of the prism is obtained and the unit of the surface area of the prism is placed in the … ….

Oblique Prism Calculator. Calculations at an oblique prism. Different to a right prism, the sides are not perpendicular to the bases (angle of slope ≠ 90°). Cavalieri's principle says, that the volume of the oblique prism is similar to that of the right prism with equal base and height. The surface area can be calculated as 2 * base area ... As you enter new dimensions into the volume calculator, a running total will also be displayed. Base Area: Height: Units: in ...The convenient to use surface area calculator will calculate this for you. FAQ How to find volume? The volume formula depends on the shape of the object. One of the most popular shapes is a rectangular prism, also known as a box, where you can simply multiply length times width times height to find its volume. Another common …Surface Area of a Prism. Surface Area = 2 × Base Area. + Base Perimeter × Length. Example: What is the surface area of a prism where the base area is 25 m 2, the base perimeter is 24 m, and the length is 12 m: Surface Area = 2 × Base Area + Base Perimeter × Length. = 2 × 25 m2 + 24 m × 12 m. = 50 m2 + 288 m2.How to Use the Pyramid Area Calculator. Our pyramid area calculator makes it easy to find the area of your pyramid. To use the calculator: Select the type of surface area you want to calculate (lateral surface area or total surface area) Enter the dimensions of your pyramid. Our calculator will automatically calculate the area of your pyramid.Oct 4, 2023 · Online calculator to calculate the surface area of geometric solids including a capsule, cone, frustum, cube, cylinder, hemisphere, pyramid, rectangular prism, sphere, spherical cap, and triangular prism Hexagonal Prism. The formula for determining the surface area of a triangular prism is defined as: w h e r e. s = a + b + c 2. S A: the surface area of the prism. a: the length of side a of the triangular base. b: the length of side b of the triangular base. c: the length of side c of the triangular base. d: the depth of the prism.The convenient to use surface area calculator will calculate this for you. FAQ How to find volume? The volume formula depends on the shape of the object. One of the most popular shapes is a rectangular prism, also known as a box, where you can simply multiply length times width times height to find its volume. Another common …The surface area of the prism is obtained by adding the areas of all the faces. The area of each pentagonal face is equal to 3.44 l², where l is the length of one of the sides of the pentagonal base. Therefore, the area of both pentagonal faces is equal to 6.8 l².On the other hand, the area of each rectangular face is equal to lh, where h is the height of the … Pentagonal prism surface area calculator, 4 days ago · The surface area of a rectangular prism calculator gives us the answer: A = 2 × l × w + 2 × l × h + 2 × w × h = 2 × 8 ft × 6 ft + 2 × 8 ft × 5 ft + 2 × 6 ft × 5 ft = 236 ft². But that is the surface area of the entire prism, and we don't want to tile it all around. After all, if we tile the top, it would be pretty difficult to get ... , Like all other polyhedrons, we can calculate the surface area and volume of a hexagonal prism. Formulas Surface Area. The formula is given below: Total Surface Area (TSA) = 6ab + 6bh, here a = apothem, b = base edge, h = height. As we know, Total Surface Area (TSA) = 2 × Base Area + Base Perimeter × height. Also,, Pentagonal Prism Surface Area Formula. P=5\cdot e\cdot\mathrm {h}+\frac {1} {2}\cdot\sqrt {5\cdot\left (5+2\cdot\sqrt {5}\right)}\cdot { e}^ {2} P = 5 ⋅ e ⋅ h + 21 ⋅ 5 ⋅ (5 + 2 ⋅ 5) ⋅ e2. …, First work out the area of the triangle. Multiply the base by the height and divide by two, (5 × 4)/2 = 10. The area of the triangular cross-section is 10 mm². Image caption, Next multiply the ..., Length (l): units. Surface Area (A): sq. units. Volume (V): cu. units. The following algorithms are included in this calculator: Volume of a Triangular Prism (V) = 1/2*b*h*l. Side (s) = √ ( (b/2)2 + h2) Surface Area of a Triangular Prism (A) = b* (h + l) + 2*l*s. Currently 4.00/5., Formula for Surface Area: The surface area of a regular pentagonal pyramid can be calculated using the following formula: A = (5/4) × l² × √(25 + 10 × √5) × h². Formula for Volume: The volume of a regular pentagonal pyramid can be calculated using the following formula: V = (5/12) × l² × h × √(5 – 2 × √5), Research shows that aid tends to flow to places that hold the relatively rich instead of poorer ones. The role of aid in Africa has been a controversial issue over the years, with ..., The convenient to use surface area calculator will calculate this for you. FAQ How to find volume? The volume formula depends on the shape of the object. One of the most popular shapes is a rectangular prism, also known as a box, where you can simply multiply length times width times height to find its volume. Another common …, A triangular prism is a geometric solid shape with a triangle as its base. It's a three-sided prism where the base and top are equal triangles and the remaining 3 sides are rectangles. This calculator finds the volume, surface area and height of a triangular prism. Surface area calculations include top, bottom, lateral sides and total surface area., Example 6: missing length in a pentagonal prism. The volume of this prism is 225 \mathrm {~cm}^2 225 cm2. Calculate the height, h h , of the prism: Write down the formula. Show step. \text {Volume of prism }=\text { Area of the base } \times \text { height} Volume of prism = Area of the base × height., Base area of a pentagonal prism $= \frac{1}{2} \times P \times a$ $= \frac{1}{2} \times 25 \times 3.4$ $= 42.5$ square units. Hence, the base area of a pentagonal prism $= 42.5$ square units. 5. Find the height of the pentagonal prism if the apothem length is 4 inches, the base length is 6 inches and its volume is 540 cubic inches. Solution:, Length (l): units. Surface Area (A): sq. units. Volume (V): cu. units. The following algorithms are included in this calculator: Volume of a Triangular Prism (V) = 1/2*b*h*l. Side (s) = √ ( (b/2)2 + h2) Surface Area of a Triangular Prism (A) = b* (h + l) + 2*l*s. Currently 4.00/5. , The following steps are used to calculate the surface area of a hexagonal prism : Step 1: Calculate the area of the hexagonal base using the formula, 3√3a 2 Step 2: Find the area of the six rectangular faces. Step 3: Add all the areas together for the total surface area of a square prism, while the area of 6 rectangular faces gives the lateral area of the square …, The steps to determine the surface area of the prism are: Step 1: Note down the given dimensions of the prism. Step 2: Substitute the dimensions in the surface area of prism formula (2 × Base Area) + (Base perimeter × height). Step 3: The value of the surface area of the prism is obtained and the unit of the surface area of the prism is placed in the …, The volume of the pentagonal prism is obtained using the formula V = 5/2 × abh. The steps to determine the volume of the pentagonal prism are: Step 1: The area of the base of the pentagonal prism is found using the formula, 5/2ab = 5/2 × 5 × 4 = 50 square feet. Step 2: The height of the prism is 6 ft. , In Texas, local entities set the rate for property taxes each fiscal year. If they raise the tax rate up past a level known as the rollback rate, taxpayers in the area can petition..., The following information can be used to calculate the surface area and volume of a regular pentagonal prism: Side length of the pentagon base (l) Height of the pentagonal prism (h) Formula for Surface Area: The surface area of a regular pentagonal prism can be calculated using the following formula: A = 5 × l × h + 2 × (5/2 × l × s), All the sides of pentagon are connected at their edges. Go through the following lines to get the various formula to compute the pentagon perimeter, area, diagonal and side. Make use of these formulae while solving the related topics. The formula to find the area of pentagon is as follows: Pentagon area = 1/4 ((√(5 (5 + 2 √5) s2), Surface Area. The surface area of a right prism is the total space occupied by its outermost faces. It is expressed in square units such as cm 2, m 2, mm 2, in 2, or yd 2. Surface area of a right prism is of 2 types. Lateral Surface Area. The lateral surface area (LSA) of a right prism is only the sum of the surface area of all its faces except ..., This geometry video tutorial explains how to calculate the surface area of a hexagonal prism. It also explains how to calculate the lateral area of a hexago..., This geometry video tutorial explains how to calculate the surface area of a hexagonal prism. It also explains how to calculate the lateral area of a hexago..., W h a t i s a p r i s m? © T Madas. Pentagonal Prism ... Total : 92 cm2. Volume : 92 x 6 = 552 cm3 ... Is there another way of calculating the volume of this prism?, All prisms are named by their bases, so the prism below is a pentagonal prism. This particular prism is called a right prism because the lateral faces are perpendicular to the bases. Oblique prisms lean to one side or the other and the height is outside the prism. Surface Area. Surface area is the sum of the areas of the faces of a …, Length (l): units. Surface Area (A): sq. units. Volume (V): cu. units. The following algorithms are included in this calculator: Volume of a Triangular Prism (V) = 1/2*b*h*l. Side (s) = √ ( (b/2)2 + h2) Surface Area of a Triangular Prism (A) = b* (h + l) + 2*l*s. Currently 4.00/5., Surface area of a triangular prism: A = 0.5 × √((a + b + c) × (-a + b + c) × (a - b + c) × (a + b - c)) + h × (a + b + c), where a, b and c are the lengths of three sides of …, Regular Pentagonal Prism Area of Base :[ ½×a×5×s ] Perimeter of Base :[ 5s ] Surface Area of Prism :[ 5as + 5sh ] Volume of Prism :[ (5/2)ash ] Enter the Apothem Length= Enter the Side Length= Enter the Height = Area of Base = Perimeter of Base = Surface Area of Prism = Volume of Prism =, The Lateral Surface Area of Pentagonal Prism formula is defined as the quantity of plane enclosed by all the lateral surfaces (that is, top and bottom faces are excluded) of the Pentagonal Prism is calculated using Lateral Surface Area of Pentagonal Prism = 5*Base Edge Length of Pentagonal Prism*Height of Pentagonal Prism. To calculate Lateral ... , A regular pentagonal prism that can be rotated, tilted, and opened into a net. 1 Part of a series of interactive plots designed to help students in geometry visualize solids and …, Step 1: Write the given dimensions of the prism. Step 2: Substitute the given values in the formula S = (2 × Base Area) + (Base perimeter × height) where "S" is the surface area of the prism. Step 3: Now solve the equation for "Base Area by simplifying the equations". , Definition. A regular prism is a specific Polyhedron characterized by regular polygons as bases, and rectangular faces . If you input the necessary variables, our calculator will give you the exact volume and surface area. Equation form: Surface Area (SA) =. n …, Learn about Pentagonal Prism Surface Area from Maths. Find all the chapters under Middle School, High School and AP College Maths. Exploring the Geometric Marvel: The Pentagonal Prism's Surface Area Quest , Total Surface area of triangular prism = 2B + Pl = (2 x Triangle area) + [ ( a + b + c ) l ] Triangle area = B =. (Apothem length = h/2) Where ( According to heron’s formula) The volume of a triangular prism = Area of base triangular prism × height. Volume of triangular prism = B x l =. Here B = Base area of the prism., Substitute the height h into the surface area of a cylinder equation: A = 2πr² + 2πrh. Bring all terms in this equation to one side to get 2πr² + 2πrh - A = 0. Note that this is a quadratic equation in terms of r. Solve this equation using the quadratic formula to obtain. r = (-2πh ± √(4π²h² + 8πA))/4π.