Question

a circle has an area of 153.86 square meters. What is the radius. ( a = pi r squared) and what is the circumference ( 2 pi r)

Answer 1

You're given the equations, just work backwards.

Answer 2

Area of a Circle = pi r^2
153.86 = pi r^2
49 = r^2
7 = r meters
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Circumference = 2 pi r
C = 2 (3.14) (7)
C = 43.96 meters