Answer:
8
Explanation:
Notice: we do not have to solve for x, and y. All we really have to do is to subtract the two equations.
(-10x + 3y) - (-4x + 7y) = 9 - 1.
Taking off the parentheses, we get:
-10x + 3y + 4x - 7y = 8.
Simplifying, we get:
-6x - 4y = 8.
So, the answer is 8.