In the triangle below ED = 5x - 10 and BC = 2x+1. Find x, ED, and BC.

Y=4x^2+x-1 solve using quadratic formula

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.

Cd is the perpendicular bisector of both xy and st, and cy=20. find xy.