Question:
Solve -79*v = -518 - 193 for v..

Answer:
9

Question:
Solve 13*i = -41*i + 2*i for i..

Answer:
0

Question:
Solve 84 = 37*d + 10 for d..

Answer:
2

Question:
Solve 12*d = -2*d + 14 for d..

Answer:
1