Expand using Pascal's triangle : `(x+y)^4`

Explanation

To expand \((x+y)^4\) using Pascal's Triangle, follow these steps:

### Step 1: Identify the Row in Pascal's Triangle
Since we are expanding \((x+y)^4\), we need to look at the 4th power, which corresponds to the 5th row of Pascal's Triangle (starting from row 0).

### Step 2: Write Out Pascal's Triangle
The first few rows of Pascal's Triangle are as follows:

...