Solve -56*b + 56 = -112 for b.
Solve this plz.

A: 3

Solve 21690*n = 21680*n + 90 for n.
Solve this plz.

A: 9

Solve -287*b + 85*b - 14*b + 2592 = 0 for b.
Solve this plz.

A:
12