question: Teacher asked me this: Solve 0 = -9*s + 2*s - 28 for s.
++++++++++
answer: -4

question: Teacher asked me this: Solve -49*z = 628 + 3048 - 736 for z.
++++++++++
answer: -60

question: Teacher asked me this: Solve 3207843*r + 860 = 3207863*r for r.
++++++++++
answer: 43

question: Teacher asked me this: Solve -5110*r - 1 = -5109*r for r.
++++++++++
answer:
-1