You can solve this by adding 3 to 2x+y=-3 so it is now 2x+y+3=0, then you can subtract y to get 2x+3=-y, multiply by -1 to get y positive so you have -2x-3=y, then insert that to the second equation as 3x+2(-2x-3)=-7 you can then multiply it out to 3x-4x-6=-7, add 6 to both sides to get 3x-4x=-1, which is the same as -x=-1 or x=1, then insert they into the upper equation to get 2+y=-3, subtract 2 and you have y=-5, so the answers are x=1 and y=-5