QUESTION: Math problem: Solve 61*s + 329 = 14*s for s.
ANS: -7
QUESTION: Math problem: Solve 0 = -999*z + 1009*z + 20 for z.
ANS: -2
QUESTION: Math problem: Solve -5*r + 11 = -6 - 23 for r.
ANS: 8
QUESTION: Math problem: Solve a = 7*a - 18 for a.
ANS:
3