Question:
Solve -53 = 55*x + 2 for x..

Answer:
-1

Question:
Solve 0 = 140*u - 187*u - 987 for u..

Answer:
-21

Question:
Solve -117 = -12063*k + 12076*k for k..

Answer:
-9

Question:
Solve -159*i + 163*i - 16 = 0 for i..

Answer:
4