### Home > MC2 > Chapter 9 > Lesson 9.1.3 > Problem 9-31

9-31.

Use the formulas for the area and circumference of a circle:

Area: π · *r*^{ 2}

Circumference: π · 2*r* or π · *d*

Area = π (8.5)^{2} = 72.25π ≈ 226.98 mm^{2}

9-31.

Use the formulas for the area and circumference of a circle:

Area: π · *r*^{ 2}

Circumference: π · 2*r* or π · *d*

Area = π (8.5)^{2} = 72.25π ≈ 226.98 mm^{2}