Answer: c) -4
Step-by-step explanation:
Get the variables on one side of 3x+y=-2x+8 and the constants on another side:
3x+y=-2x+8
(3x+y)+2x=(-2x+8)+2x
5x+y=8
Now, multiply 5x+y=8 by -2:
-2(5x+y=8)
-10x-2y=-16
Add this equation to -3x+2y=-10:
(-10x-2y=-16)+(-3x+2y=-10)
-13x=-26
x=2
Plug x=2 into -3x+2y=-10:
-3(2)+2y=-10
-6+2y=-10
2y=-4
y=-2
Therefore, (2, -2) is the solution to the system of equations, so xy=(2)(-2)=-4
