Question:
Solve -2*n = -5 - 1 for n..

Answer:
3

Question:
Solve -10*q = 7 + 3 for q..

Answer:
-1

Question:
Solve 7*l + 20 = 12*l for l..

Answer:
4

Question:
Solve -5*f + 11 = 6 for f..

Answer:
1