good catch, buddy.

it shouldn't be.

OP: in the first step, take a -1 out of -1575 to make it (-1)1575 and bring that over so that you get 1575=6*231+189 and carry it through your work.

you could just switch the signs at the end, but it depends on your teacher and how you see it.

21=-5(-1575)-34(231)

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