Answer
$x^2-2xy+y^2$
Work Step by Step
We square (expand) the binomial to obtain:
$$
(x - y)^2= (x-y)(x-y)=x^2+2\cdot x \cdot (-y)+(-y)^2=x^2-2xy+y^2
.$$
You can help us out by revising, improving and updating this answer.
Update this answerAfter you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.