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

Write down the solution for this math problem: Solve -81*x - 150 = -160*x + 64*x for x.
answer: 10

Write down the solution for this math problem: Solve -64*u + 314 = 250 for u.
answer: 1

Write down the solution for this math problem: Solve 227*l + 77*l = 61*l - 124*l + 29360 for l.
answer:
80