body{margin:0;} noscript{z-index: 10000; position: fixed; display: block; height: 100%; width: 100%; background: #fff;} noscript .fa{font-size: 40px; display:block; color: #daa520;} noscript div{margin-top: 6%; padding-left: 20px; padding-right: 20px; text-align: center;} ! You must have JavaScript enabled to use this site.

Dashboard

McGraw Hill Glencoe Geometry, 2012 View details

4. Volumes of Prisms and Cylinders

Finish the assignment

Continue to next subchapter

Exercise 58 Page 870

Recall the formula for finding the area of a circle.

7.8ft

Practice makes perfect

The area of a circle with radius r is calculated using the formula below. A=π r^2 From the exercise, we know that the area of the circle is 191ft^2. By substituting 191 for A in the formula, we can calculate r.

A=π r^2

Substitute

A= 191

191=π r^2

▼

Solve for r

DivEqn

.LHS /π.=.RHS /π.

191/π = r^2

SqrtEqn

sqrt(LHS)=sqrt(RHS)

sqrt(191/π) = r