question: Teacher asked me this: Solve -21*o + 113*o + 64*o = -98*o for o.
++++++++++
answer: 0

question: Teacher asked me this: Solve 140*l - 171 = 115*l + 154 for l.
++++++++++
answer: 13

question: Teacher asked me this: Solve -p + 237 - 226 = 0 for p.
++++++++++
answer: 11

question: Teacher asked me this: Solve 37*v + 231 = -139 for v.
++++++++++
answer:
-10