-10y + 9x = - 9....A
10y + 5x = - 5.....B
You should see right away that -10y and 10y cancel out.
We are left with
14x = -14
x = -14/14
x = -1
Plug x = -1 into EITHER equation A or B to find y.
I will use equation A.
-10y + 9(-1) = - 9
-10y - 9 = - 9
-10y = - 9 + 9
- 10y = 0
y = 0/-10
y = 0
Done!