Question

Find the lateral area of the cone in terms of π.

Answer 1

`15\pi\ cm^(2)`

Explanation:

we know that

The lateral area of the cone is equal to

`LA=\pi rl`

where

r is the radius of the base

l is the slant height

we have

`r=3\ cm`

Applying the Pythagoras Theorem find the slant height

`l^(2)=3^(2) +4^(2)\\ \\l^(2)=25\\ \\l=5\ cm`

substitute in the formula

`LA=\pi (3)(5)=15\pi\ cm^(2)`