Let's dive into this subtraction. We'll start with 87086 and subtract 8086 from it.

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

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

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

Step 4: We'll start by subtracting the digit 8 and the borrow 0 from 7 in column 4 and get -1.
We add -1 to 10 and get 9 as the next digit of the result.

Step 5: We'll start by subtracting the digit 0 and the borrow 1 from 8 in column 5 and get 7.
7 is the next digit of our result.

So, 87086 - 8086 = 79000.