We can solve this together! We're beginning with 917788944 and removing 120461645 from it.

Step 1: We'll start by subtracting the digit 5 and the borrow 0 from 4 in column 1 and get -1.
We add -1 to 10 and get 9 as the first digit of the result.

Step 2: We'll start by subtracting the digit 4 and the borrow 1 from 4 in column 2 and get -1.
We add -1 to 10 and get 9 as the next digit of the result.

Step 3: We'll start by subtracting the digit 6 and the borrow 1 from 9 in column 3 and get 2.
2 is the next digit of our result.

Step 4: We'll start by subtracting the digit 1 and the borrow 0 from 8 in column 4 and get 7.
7 is the next digit of our result.

Step 5: We'll start by subtracting the digit 6 and the borrow 0 from 8 in column 5 and get 2.
2 is the next digit of our result.

Step 6: We'll start by subtracting the digit 4 and the borrow 0 from 7 in column 6 and get 3.
3 is the next digit of our result.

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

Step 8: We'll start by subtracting the digit 2 and the borrow 0 from 1 in column 8 and get -1.
We add -1 to 10 and get 9 as the next digit of the result.

Step 9: We'll start by subtracting the digit 1 and the borrow 1 from 9 in column 9 and get 7.
7 is the next digit of our result.

So, 917788944 - 120461645 = 797327299.