Rewrite the formula for area of a circle to find the radius of a circle.
the area of a circle (a) is given by the formula where r is the circle's radius. the formula to find r is . if and , r is centimeters.

Marquise has 200 meters of fencing to build a rectangular garden. the garden's area (in square meters) as a function of the garden's width w w (in meters) is modeled by: a ( w ) = − w 2 + 1 0 0 w a(w)=−w 2 +100w what side width will produce the maximum garden area? meters