Write down the solution for this math problem: Solve 15*u + 260 = -0*u - 5*u for u.
answer: -13

Write down the solution for this math problem: Solve -2*r + 46 = 38 for r.
answer: 4

Write down the solution for this math problem: Solve -7*f - 9 + 9 = 0 for f.
answer: 0

Write down the solution for this math problem: Solve 51*f - 517672 = -515224 for f.
answer:
48