question: Teacher asked me this: Solve 68 = 9*o + 77 for o.
++++++++++
answer: -1

question: Teacher asked me this: Solve 11 = -5*z - 6*z for z.
++++++++++
answer: -1

question: Teacher asked me this: Solve 40*m + 447*m = 4870 for m.
++++++++++
answer: 10

question: Teacher asked me this: Solve -13197 = 294*m - 2613 for m.
++++++++++
answer:
-36