Answer:
it's 22 I hope you got it right if not then i'm sorry
For this case, we have the following expression:

We simplify the expression:
If we add similar terms, taking into account that different signs are subtracted and the sign of the greater one is placed, we have that 
So, we have to:

Answer:
-3x + x + 5 = -2x + 5
The midpoint is
(-4+0) / 2, (7 + (-3))/ 2 The first one is x coordinate and 2nd is the y cood)
= (-2, 2) answer
2 7.5
That’s all that I could do I hope it help