Question:
Solve 31 - 34 = -3*k for k..

Answer:
1

Question:
Solve -53*z - 21*z = -7*z + 335 for z..

Answer:
-5

Question:
Solve 52*d - 67632 = 808*d - 232*d + 885*d for d..

Answer:
-48

Question:
Solve -7 + 23 = 4*c for c..

Answer:
4