Question:
Solve -y = -31 + 30 for y..

Answer:
1

Question:
Solve 410*u = 587 - 6921 - 20726 for u..

Answer:
-66

Question:
Solve 2122*s + 398759 = 4941*s + 6043*s - 53203 for s..

Answer:
51

Question:
Solve -58*u + 135 = -31*u for u..

Answer:
5