Question: What is the solution?

Solve -664*s - 13870 = -1918 for s.

Answer: -18

Question: What is the solution?

Solve 571*n = 1287*n + 1288*n - 6012 for n.

Answer: 3

Question: What is the solution?

Solve 71*t - 2630 = -1139 for t.

Answer: 21

Question: What is the solution?

Solve 149 = 49*u - 96 for u.

Answer:
5