Question

Find the circumference and the area of a circle with a radius of 9mm.

Write your answers in terms of pi, and be sure to include the correct units in your answers.

Answer 1

Answers
Circumference = 18 π

Area = 81 π mm^2

Step by step

***answer in terms of pi which means you do NOT use the number equivalent of pi in your calculations, you leave it as the symbol π

Circumference = 2 π radius

C = (2x9) π
C = 18 π mm


Area = π radius ^2
A = 9^2 π
A = 81 π mm^2