Answer:
4in = r
Step-by-step explanation:
Different problem if the x was a variable in the question
formula for area of circle = pi x r^2.
So if the area of a circle is 16 pi in^2, it would be an obvious estimate that the radius is the square root of 16 which is 4 inches.
If the x was a variable, you would find the square root of 16x which is [tex]\sqrt{16x}[/tex] which would make it 4[tex]\sqrt{x}[/tex] as the radius.