7)
6x+4y=14 and -8x-4y=-12
If we add these two equations together we have:
6x-8x+4y-4y=14-12 combine like terms
-2x=2 divide both sides by -2
x=-1, use either origina equation to solve for y, 6x+4y=14 becomes:
6(-1)+4y=14
-6+4y=14 add 6 to both sides
4y=20 divide both sides by 4
y=5
So the solution to the system of equations is:
x=-1, y=5
8)
2x+3y=50 and 4x-2y=4
-2(2x+3y=50)+(4x-2y=4)
(-4x-6y=-100)+(4x-2y=4)
-8y=-96 divide both sides by -8
y=12, making 4x-2y=4 become:
4x-2(12)=4
4x-24=4
4x=28
x=7
So the solution to the system of equations is:
x=7, y=12