math

The formula for the surface area of a cylinder is A=2πr^2+2πrh. (A)Solve for r and simplify the result, if possible. (B) If the surface area of a cylinder is 100 square feet and the height is 40 inches, what is the radius of the cylinder in units of feet? Round your answer to the nearest tenth of a foot. (C) What is this radius in inches? Please help!!!!:(

  1. 👍
  2. 👎
  3. 👁
  1. A / (2 π) = r^2 + h r ... 0 = r^2 + h r - [A / (2 π)]

    using quadratic formula ... r = {-h ± √[h^2 - (2 A / π)]} / 2

    B) A = 100 , h = 10/3 ... plug in to find r

    C) multiply B) by 12 to get inches

    1. 👍
    2. 👎

Respond to this Question

First Name

Your Response

Similar Questions

  1. calc

    the volume of a cylindrical tin can with a top and a bottom is to be 16*pi cubic inces. if a minimum amont of tin is to be used to construct the can, what must be the height, in inches, of the can? volume of cyliner is pi*r^2*h do

  2. Math

    1. What is the surface area of the cylinder in terms of pi? The diagram is not drawn to scale. A) 990 pi in^2 B) 342 pi in^2 C) 378 pi in^2 D) 504 pi in^2 The radius is 9 and the height is 19. when I solve this, no matter what the

  3. Math

    The circumference of the base of a cylinder is 16π centimeters. The height of the cylinder is 10 centimeters.What is the surface area of the cylinder?

  4. math

    How do i find the lateral area and the surface area of a rectangular prism with the height of 8.5" the width 4" the depth 3.25" I don't want you to do it for me i want to know what formula or how i start to solve for those two

  1. Algebra 2

    Am I correct? The radius of a cylinder is 3x – 2 cm. The height of the cylinder is x + 3 cm. What is the surface area of the cylinder? Use the formula A = 2pi r2 + 2 pi rh. 2spi (3x2 + 10x – 8) 2 pi (12x2 + 7x-2) 2 pi (12x2

  2. math

    S = 2πr2 + 2πrh solve for h H=S-2πr/2πr?

  3. Math

    How to setup this equation? Find the ratio of the surface area of a cylinder to the volume of the cylinder if the height remains at 10 cm. Simplify this ratio and let f(x) = the simplified ratio. Let r be the radius of the

  4. math

    how would you find the surface area of a cylinder with 1.7m for the diameter, and 3m for the height? would you use the formula S.A = 2pi x r x h, or S.A = area of two congruent circles + area of rectangle?

  1. Math

    Cylinder A has radius r and height h. Cylinder B has radius 2r and height 2h. How many times greater is the surface area of Cylinder B than the surface area of Cylinder A? I have no idea how to start doing this problem. Are there

  2. algebra

    The surface area S of a cylinder is given by the formula S = 2 π rh + 2 πr Write the fomula for S in terms of the radius if the height of the cylinder is S more than 3 times its radius. Use the symbol for pi (distribute out and

  3. Pre-calc/trig

    Find a function that models surface area of a cylinder in terms of its height . The volume of a cylinder is 300 cm^3 . I know the volume of a cylinder is v= 3.14•r^2•h and Surface area is 2•3.14•r^2+2 •3.14•r•h. I

  4. ALGEBRA 2 HONORS

    A container is to be made in the shape of a cylinder with a conical top. The lateral surface areas of the cylinder and cone are S1 = 2(pi)rh and S2 = 2(pi)r√(r^2 + h^2). The surface area of the base of the container is B=

You can view more similar questions or ask a new question.