question: Teacher asked me this: Solve -21*b + 8*b = -26 for b.
++++++++++
answer: 2

question: Teacher asked me this: Solve -40 = -4*k - 26*k + 38*k for k.
++++++++++
answer: -5

question: Teacher asked me this: Solve 65 = 3*n + 68 for n.
++++++++++
answer: -1

question: Teacher asked me this: Solve 116*s - 439*s - 10500 = -91*s + 143*s for s.
++++++++++
answer:
-28