Write down the solution for this math problem: Solve 404 + 231 = 64*s + 63*s for s.
answer: 5

Write down the solution for this math problem: Solve -13*t - 10 = 16 for t.
answer: -2

Write down the solution for this math problem: Solve -18*x - 25 = -13*x for x.
answer: -5

Write down the solution for this math problem: Solve -50*u - 398 = -25 - 173 for u.
answer:
-4