QUESTION: Math problem: Solve 16 = -4*d - 0 for d.
ANS: -4
QUESTION: Math problem: Solve 49*k - 1500 = -10*k - 41*k for k.
ANS: 15
QUESTION: Math problem: Solve 0 = -22*z + 9*z for z.
ANS: 0
QUESTION: Math problem: Solve -21 = -11*z + 12 for z.
ANS:
3