QUESTION: Math problem: Solve -6*f = -11*f + 15 for f.
ANS: 3
QUESTION: Math problem: Solve -220 - 756 = -109*z + 1967 for z.
ANS: 27
QUESTION: Math problem: Solve -1405*k + 1413*k = 72 for k.
ANS: 9
QUESTION: Math problem: Solve -438 + 100 = 13*u for u.
ANS:
-26