Q: What is the solution?
Solve -125*f = -115*f + 50 for f.

A: -5

Q: What is the solution?
Solve 4272 = -466*r + 191*r + 97*r for r.

A: -24

Q: What is the solution?
Solve -36 = -153*l + 147*l for l.

A:
6