Q: What is the solution?
Solve -192*r - 84 = -180*r for r.

A: -7

Q: What is the solution?
Solve -5*a + 9*a + 12 = 0 for a.

A: -3

Q: What is the solution?
Solve 0 = -18*j + 112 + 14 for j.

A:
7