Question:
Solve 12*b + 15 + 21 = 0 for b..

Answer:
-3

Question:
Solve 55 = -2*f + 47 for f..

Answer:
-4

Question:
Solve 15007*w - 15636*w = -26418 for w..

Answer:
42

Question:
Solve 189*x + 5852 + 5299 = 602*x for x..

Answer:
27