Question

which equation could be used to find the area in square centimeters of. a radius of 26 centimeters

Answer 1

I'm assuming you're talking about the area of a square, which is $\pi r$².
Plug in the radius, 26 cm, for r.
$\pi 26$²  <<equation

If you want the answer, $\pi 26$² = 2,123.7 cm²