Solve 4409 = -1049*f + 14899 for f.
Solve this plz.

A: 10

Solve -115*t = -170*t + 109*t + 329 + 481 for t.
Solve this plz.

A: -15

Solve -54 = -29*r + 23*r for r.
Solve this plz.

A:
9