SOLUTION: What is the radius of a circle whose area is 719 square feet?

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Question 452973: What is the radius of a circle whose area is 719 square feet?
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
A=pi%2Ar%5E2 Start with the area of a circle formula.


A%2Fpi=r%5E2 Divide both sides by pi.


sqrt%28A%2Fpi%29=r Take the square root of both sides to isolate "r" (note: we're only taking the positive square root since a negative radius doesn't make sense)


r=sqrt%28A%2Fpi%29 Flip the equation.


r=sqrt%28719%2Fpi%29 Plug in A=719.


r=sqrt%28719%2F3.14159265%29 Replace pi with 3.14159265 (note: Use more digits of pi to get better accuracy).


r=sqrt%28228.864808427662%29 Divide (this figure is approximate).


r=15.1282784356866 Take the square root of 228.864808427662 to get 15.1282784356866 (again, this is approximate).


r=15.128 Round to the nearest thousandth.


So the radius is approximately 15.128 ft.