QUESTION: Math problem: Solve 30*r + 38 - 41 = -4*r + 65 for r.
ANS: 2
QUESTION: Math problem: Solve -17 = -13*n + 30*n for n.
ANS: -1
QUESTION: Math problem: Solve -29*k + 64*k + 315 = 0 for k.
ANS: -9
QUESTION: Math problem: Solve 55*d = -86 - 24 for d.
ANS:
-2