How do you solve the equation n^2-10n=21 by factoring?

Consider the table below. x y -1 -5 0 5 1 11 2 13 3 11 complete the standard form equation representing the quadratic relationship displayed above, where a, b, and c are constants.

The diameter of a ball is 8 in. what is the volume of the ball? use 3.14 for pi. enter your answer as a decimal in the box. round only your final answer to the nearest hundredth.

I’m stuck on this equation, anyone got the answer?