Kelly made a blueberry pie. After measuring the pie tin, Kelly calculated it has an area of 78.5 square inches. What is the pie tin's diameter? (Using 3.14 as pi)

The radius is 5 in

Step-by-step explanation:

The area of a circle is given by the formula

A = pi * r^2

We know the area = 78.5 in^2 (volume would be in^3 area is in^2)

78.5 = 3.14*r^2

Divide each side by 3.14

78.5/3.14 = 3.14/3.14*r^2

25 = r^2

Take the square root of each side

sqrt (25) sqrt (r^2)

5 = r