Question

the circumference of a circle is 20 pie ft. what is the area in square feet? express your answers in terms of pie

Answer 1

Explanation:

Circumference = 2 pi r re-arrange to :

r = circumference / 2pi Sub into the area equation below:

Area = pi r^2 = pi ( circumference/(2pi) )^2

Area = pi * ( 20 pi / (2pi) ) ^2

= 100 pi ft^2