2x+y=-10 Multiply both side by 3 2x*3+y*3=-10*3 6x+3y=-30
3x-y=0 Multiply both side by 2 3x*2-y*2=0*2 6x-2y=0 Next, use substitute property 6x+3y=-30 - 6x-2y=0 = y=-30 3x-y=0 Substitute y with -30 3x-30=0 Add 30 to each side 3x-30+30=0+30 3x=30 Divided both side by 3 3x/3=30/3 x=10, so the solution pair is (10,-30). In this case, there is the first way to solve these two equation. Then, I would use equation 3x+1.5y=-15 in this question by multiply 2x+y=-10 by multiplying both side by 3/2 to eliminate x and to solve variables for y. Hope it help!
