Write down the solution for this math problem: Solve 8*r + 15 = -9 for r.
answer: -3

Write down the solution for this math problem: Solve u + 4*u + 0*u + 60 + 270 = 0 for u.
answer: -66

Write down the solution for this math problem: Solve 1 - 4 = 3*n for n.
answer: -1

Write down the solution for this math problem: Solve 15*s + 1 = 14*s for s.
answer:
-1