### Home > GC > Chapter 8 > Lesson 8.3.3 > Problem 8-107

8-107.

Use what you know about the area and circumference of circles to answer the questions below. Show all work. Leave answers in terms of *π*.

If the radius of a circle is

units, what is its circumference? What is its area? Remember that the area of a circle is

, while the circumference of a circle is. area =

circumference =If a circle has diameter

units, what is its circumference? What is its area? Use the formulas given in part (a). What is the radius of this circle?

If a circle has circumference

units, what is its area?

Solve for the radius then use the radius to calculate the area.