Question: What is the solution?

Solve 0 = 259*b - 160*b - 1089 for b.

Answer: 11

Question: What is the solution?

Solve -1999 = -3378*f + 13287 + 29935 + 5449 for f.

Answer: 15

Question: What is the solution?

Solve -18*u - 58 = -130 for u.

Answer: 4

Question: What is the solution?

Solve -19819 = 398*h - 15839 for h.

Answer:
-10