comparing Pythagorean theorem to the equation of a circle

Pythagorean theorem is related to the equation of a circle because you can use Pythagorean theorem to find the equation of a circle. the radius from the equation of a circle is the hypotenuse (c squared) used in the Pythagorean theorem formula. the x and y sides in Pythagorean theorem are the same as the h and k numbers you plug into the equation of a circle.