Question: What is the solution?

Solve 12*u - 30 = 18*u for u.

Answer: -5

Question: What is the solution?

Solve -9*z + 3 = -6*z for z.

Answer: 1

Question: What is the solution?

Solve x - 70*x - 426 - 195 = 0 for x.

Answer: -9

Question: What is the solution?

Solve 167*r = -789 - 2126 - 1093 for r.

Answer:
-24