## Elementary Technical Mathematics

$r=5.35ft$
We use the formula for the area of a circle $A=\pi*r^{2}$ and solve for $r$ to find the radius. We have the area: $A=90ft^{2}$ thus: $A=\pi*r^{2}$ $r=\sqrt {\frac{A}{\pi}}=\sqrt {\frac{90ft^{2}}{\pi}}=5.35ft$