### Home > MC1 > Chapter 9 > Lesson 9.3.2 > Problem9-138

9-138.

Find the area of each of the circles described below. Express your answers accurately to the nearest hundredth.

1. A circular mirror with a radius of $3$ centimeters.

Remember that a circle's area is equal to $πr ^{2}$, where $r$ is the radius.

$π\left(3\right)^{2} = π\left(9\right) = 9π ≈ 28.26$ sq cm.

2. A circular dinner plate with a diameter of $9$ inches. (Start by finding the radius.)

The radius is equal to half the diameter. Remember to check your work.