Let's get this math done. We have 5623 and 1351 and we're going to add them all together.

Step 1: We'll start by adding the digits 3 & 1 in column 1 and get 4.

Step 2: We'll start by adding the digits 2 & 5 in column 2 and get 7.

Step 3: We'll start by adding the digits 6 & 3 in column 3 and get 9.

Step 4: We'll start by adding the digits 5 & 1 in column 4 and get 6.

So, 5623 + 1351 = 6974.

