In the diagram, the radius of the outer circle is 2x em and the radius of the inside circle is 6 cm. The area of the shaded region is 220 cm? What is the value of x2

8 (second choice)

Step-by-step explanation:

Area of a Circle

Given a circle of radius r, the area is calculated by the formula:

There are two circles in the diagram. The outer circle has a radius of r1=2x, thus its area is:

The interior circle has a radius of r2=6 cm, thus its area is:

The shaded area is obtained by subtracting A1-A2:

The value of the shaded area is given as 220π cm2. Equating:

Dividing by π:

Adding 36:

Taking square root:

Dividing by 2:

x = 8 cm

8 (second choice)