When you first use the elimination method, you would multiply 2x-y = 10 by -2 so that you could get the 4x to be eliminated.
4x-3y = 22
(2x-y = 10)-2 = -4x + 2y = -20
When you add those 2 together you are left with -y = 2, which you divide by negative to get y = -2. Then you substitute -2 for y to solve for x. I substituted the bottom equation