Решение:
- \(-a+b+2a-3b = (-a+2a) + (b-3b) = a - 2b\)
- \(4x-3y-x+y = (4x-x) + (-3y+y) = 3x - 2y\)
- \(25k-12n+7k+7n+12n = (25k+7k) + (-12n+7n+12n) = 32k + 7n\)
- \(0,5m+2z+5m-4z-5m = (0,5m+5m) + (2z-4z) = 5,5m - 2z\)
Ответ: 1) a - 2b; 2) 3x - 2y; 3) 32k + 7n; 4) 5,5m - 2z.