Solve 3*a = -20 + 32 for a.
Solve this plz.

A: 4

Solve -43*k + 17*k - 156 = 0 for k.
Solve this plz.

A: -6

Solve -31300*w = -31344*w - 2237 + 477 for w.
Solve this plz.

A:
-40