Question

how do you find the area of a circle with a circumference of 42

Answer 1

area = pi(r^2)

circumference = 2pi(r)

solve the circumference for "r" and use it in the area...

Answer 2

Do you mean 42pi for circumference? or just 42?

42 = 2pi(r)

r = 21/pi

A = pi(2/pi)^2

A = pi(2)(2)
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pi(pi)

A = 4/pi

Answer 3

42pi = 2pi(r)

r = 21

A = pi(r^2)

A = pi(21^2)

A = 441..if I did it right in me head