To subtract 805 from 1090, we can use the column subtraction method. Starting with the units digit, we subtract 5 from 0. Since 0 is smaller than 5, we borrow 1 from the tens digit, making it 8, and the units digit becomes 10. 10 minus 5 is 5. Next, we subtract 0 from 8 in the tens digit, resulting in 8. Finally, we subtract 8 from 10 in the hundreds digit, resulting in 2. Therefore, 1090 - 805 = 285.