To express the surface area of a sphere (SA) in terms of the radius \( r \), you can start with the original formula:
\[ SA = 4\pi r^2 \]
To solve for \( r \), follow these steps:
- Divide both sides by \( 4\pi \):
\[ \frac{SA}{4\pi} = r^2 \]
- Take the square root of both sides to solve for \( r \):
\[ r = \sqrt{\frac{SA}{4\pi}} \]
Thus, the equation that shows the formula for the radius \( r \) in terms of the surface area \( SA \) is:
\[ r = \sqrt{\frac{SA}{4\pi}} \]