OK, let's do this. We've got 81804 and 64432, and we're subtracting the second number from the first.

Step 1: We'll start by subtracting the digit 2 and the borrow 0 from 4 in column 1 and get 2.
2 is the first digit of our result.

Step 2: We'll start by subtracting the digit 3 and the borrow 0 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 4 and the borrow 1 from 8 in column 3 and get 3.
3 is the next digit of our result.

Step 4: We'll start by subtracting the digit 4 and the borrow 0 from 1 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 6 and the borrow 1 from 8 in column 5 and get 1.
1 is the next digit of our result.

So, 81804 - 64432 = 17372.