# What is the area of a semicircle with radius #8# cm?

##### 1 Answer

Consider a circle of radius

Here's a diagram of what's going on.

Before applying the formula, let's convert

We will now use the formula to determine the area of this semi-circle.

We can confirm this using the formula for area of a semi-circle,

Same, so both formulae work.

Here are a few problems for you practice.

**Practice exercises:**

Determine the area of the following semi-circles.

a) The semi-circle contained inside a circle of radius

b) The semi-circle contained inside a circle of diameter

c) The semi-circle contained inside a circle of circumference

Hopefully this helps, and good luck!