Question:
Solve -90*a - 43*a - 29857 + 31453 = 0 for a..

Answer:
12

Question:
Solve -669*y - 3788 = -5301 - 8522 for y..

Answer:
15

Question:
Solve -20689 = 1633*u - 416*u for u..

Answer:
-17

Question:
Solve 137*o + 873 = -1939 - 1161 for o..

Answer:
-29