Question: What is the solution?

Solve 68*u = 75*u - 7 for u.

Answer: 1

Question: What is the solution?

Solve 40*k = 8 + 112 for k.

Answer: 3

Question: What is the solution?

Solve -45*b = 84*b + 120*b + 9*b - 516 for b.

Answer: 2

Question: What is the solution?

Solve -3*o = 5*o - 8 for o.

Answer:
1