simplify: 3x - [3y - {2x - (y - x)}]

Explanation

To simplify the expression \( 3x - [3y - \{2x - (y - x)\}] \), we will follow the order of operations, starting from the innermost brackets and working our way outwards.

### Step-by-Step Solution:

1. **Identify the innermost bracket**: The innermost expression is \( (y - x) \).

**Hint**: Start simplifying from the innermost brackets and work your way out.

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