Question: What is the solution?

Solve 1103*r + 55771 = 2400*r for r.

Answer: 43

Question: What is the solution?

Solve 0 = 631*o - 628*o + 15 for o.

Answer: -5

Question: What is the solution?

Solve 43*f - 352*f = 568*f + 14909 for f.

Answer: -17

Question: What is the solution?

Solve -4224*z + 4215*z - 126 = 0 for z.

Answer:
-14