Okay, let's tackle this math problem. We're starting with 51091 and subtracting 41641.

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

Step 2: We'll start by subtracting the digit 4 and the borrow 0 from 9 in column 2 and get 5.
5 is the next digit of our result.

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

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

So, 51091 - 41641 = 9450.