Question: What is the solution?

Solve 399 - 423 = 2*v for v.

Answer: -12

Question: What is the solution?

Solve 166*u - 169*u = 30 for u.

Answer: -10

Question: What is the solution?

Solve 59*f - 52*f - 14 = 0 for f.

Answer: 2

Question: What is the solution?

Solve 3262754*f + 60 = 3262757*f for f.

Answer:
20