Question:
Solve -40*f - 27*f - 11 + 11 = 0 for f..

Answer:
0

Question:
Solve 0 = -z - 0 + 5 for z..

Answer:
5

Question:
Solve -11 = -2*r - 7 for r..

Answer:
2

Question:
Solve 111*u + 8 = 113*u for u..

Answer:
4