I need help finding the value of n

Solve each quadratic equation by factoring and using the zero product property. x^2 - 8x + 30 = 3x

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

I’m confused on how to work the pie charts