What is the formula to find radius of the circle

Adriver from the university of florida women’s swimming and diving team is competing in the in ncaa zone b championships

If the discriminant if a quadratic equation is 4 which statement describes the roots?

If the endpoints of the diameter of a circle are (8, 6) and (2,0), what is the standard form equation of the circle? a) (x + 5)2 + (y + 3)2 = 18 (x + 5)2 + (y + 3)2 = 3.72 (x - 5)2 + (y - 3)2 = 18 d) (x - 5)2 + (y - 3)2 = 32