51. In the figure below, a square is inscribed in a circle of radius r. What is the perpendicular distance from the center of the circle to a side of the square, in terms of r ?

Answer and Explanation

Your Answer is

Correct Answer is B

Explanation

Draw a perpendicular to one side of the square through the center of the circle. Connecting the center of the circle to one of the endpoints on this side of the square results in an isosceles right triangle. According to the Pythagorean theorem, the distance from the center of the circle to the side of the square can be calculated as B.