Question: What is the solution?

Solve 0 = -31*k - 1313 + 631 for k.

Answer: -22

Question: What is the solution?

Solve -13374*s + 396 = -13572*s for s.

Answer: -2

Question: What is the solution?

Solve -9*a = -17*a + 80 for a.

Answer: 10

Question: What is the solution?

Solve 0*k + 46 = -9*k + 10 for k.

Answer:
-4