Q: What is the solution?
Solve -9*z = -2*z + 7 for z.

A: -1

Q: What is the solution?
Solve -210*h + 3457 - 8077 = 0 for h.

A: -22

Q: What is the solution?
Solve 12*n = 14*n + 2 for n.

A:
-1