Q: Solve:
Solve 21*h - 15*h = 6 - 72 for h.

A: -11

Q: Solve:
Solve -1065*l - 264290 = 639*l + 146*l + 620*l for l.

A: -107

Q: Solve:
Solve -30*i + 26*i - 16 = 0 for i.

A:
-4