Question: What is the solution?

Solve -2*u - 20 = -12 for u.

Answer: -4

Question: What is the solution?

Solve -1403*a - 12335 + 81082 = 0 for a.

Answer: 49

Question: What is the solution?

Solve 1180*r - 413*r = 11505 for r.

Answer: 15

Question: What is the solution?

Solve 0 = 48*z + 227 - 419 for z.

Answer:
4