question: Teacher asked me this: Solve -29*f - 89 - 47 + 20 = 0 for f.
++++++++++
answer: -4

question: Teacher asked me this: Solve -68*s + 31 - 31 = 0 for s.
++++++++++
answer: 0

question: Teacher asked me this: Solve -22*k + 83 + 238 - 167 = 0 for k.
++++++++++
answer: 7

question: Teacher asked me this: Solve 129*d - 320 = 169*d for d.
++++++++++
answer:
-8