question: Teacher asked me this: Solve 66 = -77*f - 11 for f.
++++++++++
answer: -1

question: Teacher asked me this: Solve 4*x - 26*x = 12*x for x.
++++++++++
answer: 0

question: Teacher asked me this: Solve -477*s + 1806*s + 191784 = 17685 for s.
++++++++++
answer: -131

question: Teacher asked me this: Solve -2*u - 13 + 23 = 0 for u.
++++++++++
answer:
5