Solve -21*a - 1683 = 111*a - 33*a for a.
Solve this plz.

A: -17

Solve 27 = -18*c - 27 for c.
Solve this plz.

A: -3

Solve 26*m - 2102 = 118*m - 538 for m.
Solve this plz.

A:
-17