Question

Find the total surface area of the following cone. Leave your answer in terms of Pi. 4cm 3cm

Answer 1

The triangle formed from the height of the cone and the radius of its base is a special 3,4,5 triangle. The slant height is 5cm.

Recall that the area of a circle = pi*r^2

Substitute 3 in for r

Area = pi * (3)^2 = 9pi

SA = pi*r*l + B

Substitute our values into the equation

SA = pi * 3 * 5 + 9pi

SA = 15pi + 9pi

SA = 24pi cm^2