Question:
Solve 10*k - 56 = -4*k for k..

Answer:
4

Question:
Solve 68*v = 162*v + 114*v + 321 + 303 for v..

Answer:
-3

Question:
Solve -137865 = -1149*o - 2179*o - 207*o for o..

Answer:
39

Question:
Solve 838*w + 20 = 818*w for w..

Answer:
-1