At each step, you borrow a single monomial from the dividend. You first write x^2 in the answer space, multiply x^2 by (x - 2) and subtract the result from the first two monomials of the dividend. This leaves -x^2. At this point, you borrow a single monomial: 12x and write -x^2 + 12x instead of -x + 12x - 5. Then you write -x in the answer space, multiply -x by (x - 2) and subtract the result from -x^2 + 12x. Only at this point you borrow the final monomial from the dividend: -5. Then you perform one more step.