Question:
Solve 0 = -1067*x + 1006*x + 1220 for x..

Answer:
20

Question:
Solve -3*u = -8 + 23 for u..

Answer:
-5

Question:
Solve 0 + 9 = -3*a for a..

Answer:
-3

Question:
Solve -15*k - 81 = -21 for k..

Answer:
-4