8x + 9y = -5
-8x - 9y = 5
The simplest method to use in this instance is the elimination method, as all variable terms' coefficients are opposites of each other. If you add these equations together, they will cancel out.
8x + 9y = -5
-8x - 9y = 5
+__________
0 - 0 = 0
0 = 0
Since these two equations cancel each other out, this system has infinitely many solutions.
Answer:
b: infinitely many solutions