(V15 - V20)- V5;

It seems like you are referencing a mathematical or algebraic expression involving variables labeled V15, V20, and V5.

To simplify the expression \( (V15 - V20) - V5 \), you can follow these steps:

1. Combine the Terms: Start with the expression: \[ (V15 - V20) - V5 \]

2. Distribute: This expression simplifies to: \[ V15 - V20 - V5 \]

So the final simplified expression is: \[ V15 - V20 - V5 \]

If you need further assistance or if V5, V15, or V20 represents specific values or functions, please provide more details!