Question: What is the solution?

Solve 0 = 35*a - 42*a - 21 for a.

Answer: -3

Question: What is the solution?

Solve 0 = -12*x - 957 + 873 for x.

Answer: -7

Question: What is the solution?

Solve -770 = -8*q - 834 for q.

Answer: -8

Question: What is the solution?

Solve 7*v = 2*v for v.

Answer:
0