Alright, ready to do some subtraction? We're taking 203689 and subtracting 56400 from it.

Step 1: We'll start by subtracting the digit 0 and the borrow 0 from 9 in column 1 and get 9.
9 is the first digit of our result.

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

Step 3: We'll start by subtracting the digit 4 and the borrow 0 from 6 in column 3 and get 2.
2 is the next digit of our result.

Step 4: We'll start by subtracting the digit 6 and the borrow 0 from 3 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 5 and the borrow 1 from 0 in column 5 and get -6.
We add -6 to 10 and get 4 as the next digit of the result.

Step 6: We'll start by subtracting the digit 0 and the borrow 1 from 2 in column 6 and get 1.
1 is the next digit of our result.

So, 203689 - 56400 = 147289.