Question: What is the solution?

Solve 60*d - 5*d + 55 = 0 for d.

Answer: -1

Question: What is the solution?

Solve 35*q - 45*q = -42*q - 192 for q.

Answer: -6

Question: What is the solution?

Solve 0 = 21*i - 63 + 84 for i.

Answer: -1

Question: What is the solution?

Solve -12*q + 16 = 16 - 72 for q.

Answer:
6