Q: What is the solution?
Solve -3*r + 78 = 81 for r.

A: -1

Q: What is the solution?
Solve 14*c - 992 + 1308 = 596 for c.

A: 20

Q: What is the solution?
Solve 64 - 30 = 5*z + 74 for z.

A:
-8