Question:
Solve 0 = z - 7*z - 12 for z..

Answer:
-2

Question:
Solve -138*l + 272*l = 2948 for l..

Answer:
22

Question:
Solve -474*i + 99*i + 3739 = -4136 for i..

Answer:
21

Question:
Solve -6*y + 10 = -4*y for y..

Answer:
5