|-6 4/5|+|5,75|

To solve \(-6 \frac{4}{5} + 5.75\), we first need to convert both numbers to a common format (either mixed numbers or decimals).

1. Convert -6 \(\frac{4}{5}\) to a decimal: \[ -6 \frac{4}{5} = -6 - \frac{4}{5} = -6 - 0.8 = -6.8 \]

2. Convert 5.75 to decimal form: \[ 5.75 = 5.75 \]

3. Now calculate the absolute values and then add: \[ |-6.8| = 6.8 \] \[ |5.75| = 5.75 \]

4. Add the absolute values: \[ 6.8 + 5.75 = 12.55 \]

So, the final answer is \(12.55\).