Solve -14681*u = -14687*u + 30 for u.
Solve this plz.

A: 5

Solve -3316*f + 6491*f - 7526 = 3246*f for f.
Solve this plz.

A: -106

Solve 0 = -4*d + 9*d - 20 for d.
Solve this plz.

A:
4