SOLUTION: Find the radius of a sphere with surface area 160in squared. use the formula A=4(pi)(r)squared where A is the surface area and r is the radius of the sphere.

Algebra ->  Quadratic Equations and Parabolas  -> Quadratic Equations Lessons -> SOLUTION: Find the radius of a sphere with surface area 160in squared. use the formula A=4(pi)(r)squared where A is the surface area and r is the radius of the sphere.      Log On


   

Question 35563: Find the radius of a sphere with surface area 160in squared. use the formula A=4(pi)(r)squared where A is the surface area and r is the radius of the sphere.
Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
The surface area (A) of the sphere is given as 160 sq.in., so we can write:
4%28pi%29r%5E2+=+160 Solve this for r. Divide both sides of the equation by4%28pi%29
r%5E2+=+160%2F4%28pi%29 Now take the square root of both sides.
r+=+sqrt%28160%2F4%28pi%29%29 Simplify.
r+=+%28sqrt%28160%29%29%2Fsqrt%284%28pi%29%29
r+=+%28sqrt%2816%2A10%29%29%2Fsqrt%284%28pi%29%29
r+=+%284sqrt%2810%29%29%2F2sqrt%28pi%29
r+=+2sqrt%2810%29%2Fsqrt%28pi%29