Question:
Solve -1 = -5*l + 4 for l..

Answer:
1

Question:
Solve 5 = 28*u + 33 for u..

Answer:
-1

Question:
Solve -17 = 13*c - 381 for c..

Answer:
28

Question:
Solve -61*j + 68*j + 28 = 0 for j..

Answer:
-4