The problem you shared asks to solve the equation $A = \pi r^2$ for $r$, where $A$ is the area of a circle, and $r$ is its radius.

Starting with the equation: $A = \pi r^2$

To solve for $r$, follow these steps:

1. Divide both sides by $\pi$: $\frac{A}{\pi} = r^2$

2. Take the square root of both sides: $r = \sqrt{\frac{A}{\pi}}$

This means that the correct answer is option c from the choices, not the circled answer.

Would you like more details on this problem or have any additional questions?

Here are 5 related questions you can try:

1. How would you solve $A = 4\pi r^2$ (surface area of a sphere) for $r$?
2. If the area of a circle is 100 square units, what is the radius?
3. What happens to the radius if you double the area of the circle?
4. How can you express the diameter of a circle in terms of its area?
5. If the circumference of a circle is $2\pi r$, how would you solve for $r$?

Tip: When dealing with geometry, always pay attention to units of measurement for area, radius, and circumference!