Question: What is the solution?

Solve 3 = -2*x + 3*x for x.

Answer: 3

Question: What is the solution?

Solve -100*r - 1319 - 1275 = 106 for r.

Answer: -27

Question: What is the solution?

Solve 8250 + 4544 = 1080*x - 3406 for x.

Answer: 15

Question: What is the solution?

Solve 889*u - 5598 = 8626 for u.

Answer:
16