question: Teacher asked me this: Solve -311*k - 1938 + 8469 = 0 for k.
++++++++++
answer: 21

question: Teacher asked me this: Solve -71*d - 42*d = 347*d - 3220 for d.
++++++++++
answer: 7

question: Teacher asked me this: Solve 42 = -3511*c + 3517*c for c.
++++++++++
answer: 7

question: Teacher asked me this: Solve 25*f + 4*f + 6 = 31*f for f.
++++++++++
answer:
3