Q: Solve:
Solve 0 = -9*r + 1138 - 1219 for r.

A: -9

Q: Solve:
Solve -19*h = 22*h + 492 for h.

A: -12

Q: Solve:
Solve -35*c - 36*c = 42*c - 99*c + 686 for c.

A:
-49