Solve 4021 - 5275 = -66*c for c.
Solve this plz.

A: 19

Solve -1506 - 3278 = 77*r + 107*r for r.
Solve this plz.

A: -26

Solve 64*i + 36*i - 2313 = 987 for i.
Solve this plz.

A:
33