Question:
Solve -105 = 17*q - 139 for q..

Answer:
2

Question:
Solve -486*z - 16796 + 6590 = 0 for z..

Answer:
-21

Question:
Solve 575*f = 939*f - 5824 for f..

Answer:
16

Question:
Solve -5*t = -18*t - 13 for t..

Answer:
-1