## College Algebra 7th Edition

The area of this circle can be expressed as: $r$ = $\sqrt \frac{A}{\pi}$, $r\gt0$
The area of a circle is given by the following formula: $A$ = $\pi$$r^{2}$ Now, we solve for $r$: First, divide both sides by $\pi$: $\frac{A}{\pi}$ = $r^{2}$ Then, we take the square root of r: $r$ = $\sqrt \frac{A}{\pi}$ Since we are talking about length, we can only use those values of $r$ that are positive. So we can express the function for the area of this circle in the following way: $r$ = $\sqrt \frac{A}{\pi}$, $r\gt0$