Solve -964*f - 990 = -1074*f for f.
Solve this plz.

A: 9

Solve -35*r = 72*r - 749 for r.
Solve this plz.

A: 7

Solve 9686*z + 81 = 9611*z - 294 for z.
Solve this plz.

A:
-5