A cylinder has a surface area of 80π in2. The radius is 4 inches. Find the height.

6 in

Step-by-step explanation:

80π = 2πr * (r+h)

80π = 2π * 4 * (4+h)

4 + h = 10

h = 6

The height is 6 inches

Step-by-step explanation:

The surface area of a cylinder is given by

SA = 2 pi r^2 + 2 pi rh where r is the radius and h is the height

Substituting what we know

80pi = 2 pi (4) ^2 + 2 pi * 4 * h

80pi = 32 pi + 8 pi h

Divide each side by pi

80 = 32 + 8 h

Subtract 32 from each side

80-32 = 8h

48 = 8h

Divide each side by 8

6 = h