question: Teacher asked me this: Solve 30 = 30*r - 24*r for r.
++++++++++
answer: 5

question: Teacher asked me this: Solve -o + 13 = 16 for o.
++++++++++
answer: -3

question: Teacher asked me this: Solve -353 = -45*p + 19*p + 89 for p.
++++++++++
answer: 17

question: Teacher asked me this: Solve 0 = -51*f + 620 + 345 - 251 for f.
++++++++++
answer:
14