Question

the equation for the area of a circle is (a = pi r^{2}). the variable (a) represents the area and (r) represents the radius of the circle. solve the equation for the radius, (r). assume the radius is positive.

Explanation:

Step1: Isolate $r^{2}$

Divide both sides of $A = \pi r^{2}$ by $\pi$. We get $\frac{A}{\pi}=r^{2}$.

Step2: Solve for $r$

Take the square - root of both sides. Since $r>0$, we have $r = \sqrt{\frac{A}{\pi}}$.

Answer:

$r=\sqrt{\frac{A}{\pi}}$