Here we go! We're going to add 4579 and 7709 together.

Step 1: We'll start by adding the digits 9 & 9 in column 1 and get 18.
We'll write down the last digit 8 and carry the 1 to the next column.

Step 2: We'll start by adding the digits 7 & 0 in column 2 and get 8.

Step 3: We'll start by adding the digits 5 & 7 in column 3 and get 12.
We'll write down the last digit 2 and carry the 1 to the next column.

Step 4: We'll start by adding the digits 4 & 7 in column 4 and get 12.
We'll write down the last digit 2 and carry the 1 to the next column.

So, 4579 + 7709 = 12288.

