Sure thing! We've got 90400 and 43029, and we're going to subtract the second number from the first.

Step 1: We'll start by subtracting the digit 9 and the borrow 0 from 0 in column 1 and get -9.
We add -9 to 10 and get 1 as the first digit of the result.

Step 2: We'll start by subtracting the digit 2 and the borrow 1 from 0 in column 2 and get -3.
We add -3 to 10 and get 7 as the next digit of the result.

Step 3: We'll start by subtracting the digit 0 and the borrow 1 from 4 in column 3 and get 3.
3 is the next digit of our result.

Step 4: We'll start by subtracting the digit 3 and the borrow 0 from 0 in column 4 and get -3.
We add -3 to 10 and get 7 as the next digit of the result.

Step 5: We'll start by subtracting the digit 4 and the borrow 1 from 9 in column 5 and get 4.
4 is the next digit of our result.

So, 90400 - 43029 = 47371.