Question:
Solve 13*d + 5 - 51 - 19 = 0 for d..

Answer:
5

Question:
Solve n + 7*n = 4*n for n..

Answer:
0

Question:
Solve -56*s + 52*s + 16 = 0 for s..

Answer:
4

Question:
Solve -962*v + 964*v = -12 for v..

Answer:
-6