Question 1165711
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Why is the signs when factoring the difference of 2 squares a sum and a difference
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Why  for real numbers x and y, {{{(x+y)(x-y)=(x+y)x-(x+y)y=x^2+xy-xy-y^2=x^2+0-y^2=x^2-y^2}}} ?


According to those steps, {{{x^2-y^2=(x+y)(x-y)}}}.