Question: What is the solution?

Solve -72*n - 12 = -47*n + 138 for n.

Answer: -6

Question: What is the solution?

Solve 131*z + 20*z - 1704 = 9*z for z.

Answer: 12

Question: What is the solution?

Solve -4*y + 229 - 249 = 0 for y.

Answer: -5

Question: What is the solution?

Solve 0 = -4*k - k + 5 for k.

Answer:
1