Question: What is the solution?

Solve -x - 49 + 47 = 0 for x.

Answer: -2

Question: What is the solution?

Solve 3179 = 100*u + 10079 for u.

Answer: -69

Question: What is the solution?

Solve -2*b = -323 + 313 for b.

Answer: 5

Question: What is the solution?

Solve -2107*d + 1419*d - 22188 = -1204*d for d.

Answer:
43