Whats the root of the square 0 = x2 - 4x - 12

Asap 25 pts + brainliest to right/best answer

Select the number of ways in which a line and a circle can intersect

Aclassmate thinks that solving a system by graphing gives an exact answer when the lines appear to cross at a grid point, but only an approximate answer when they don't. explain why this isn't true.