Write down the solution for this math problem: Solve -8*k + 171 = 195 for k.
answer: -3

Write down the solution for this math problem: Solve 735*s = 86*s - 1704 + 10162 + 8416 for s.
answer: 26

Write down the solution for this math problem: Solve -40*x - 1 = -39*x for x.
answer: -1

Write down the solution for this math problem: Solve u - 65 = -66 for u.
answer:
-1