Question:
Solve -12650 = -189*f - 8870 for f..

Answer:
20

Question:
Solve -99*k = 27*k - 16*k for k..

Answer:
0

Question:
Solve 3 = 2*z + 1 for z..

Answer:
1

Question:
Solve -12*d - 27 + 75 = 0 for d..

Answer:
4