The next two systems do NOT have opposite like terms.

Answer:
x = 0
y = -1
Step-by-step explanation:
Multiply second equation with -1
(-1) * (-3x - 8y) = 8
3x + 8y = -8 now find its sum with the first equation
2x - 8y + 3x + 8y = 8 - 8 add like terms (note that minus 8y will eliminate +8y)
x = 0 to find the value of y replace the x with 0 in the first equation
2*0 - 8y = 8
-8y = 8 divide both sides by -8
y = -1