Question 1041607
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Do you know this identity

(x+y)*(x-y) = {{{x^2 - y^2}}}.

It is valid for all real numbers x and y.

If you don't know it or if you are not sure, see the lesson <A HREF=https://www.algebra.com/algebra/homework/Polynomials-and-rational-expressions/The-difference-of-squares-formula.lesson>The difference of squares formula</A> in this site.
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