6,4а-5b-(-4,6b+5,3a)

To simplify the expression \( 6.4a - 5b - (-4.6b + 5.3a) \), follow these steps:

1. Distribute the negative sign into the parentheses: \[ 6.4a - 5b + 4.6b - 5.3a \]

2. Combine like terms:

   • For the \( a \) terms: \( 6.4a - 5.3a = 1.1a \)
   • For the \( b \) terms: \( -5b + 4.6b = -0.4b \)

3. Combine the results: \[ 1.1a - 0.4b \]

Thus, the simplified expression is: \[ 1.1a - 0.4b \]