Question

(5x^2-xy+3y^2)-(4x^2 + xy+2y^2)

Answer 1

$(5x^{2}-xy+3y^{2})-(4x^{2}+xy+2y^{2})=5x^{2}-xy+3y^{2}-4x^{2}-xy-2y^{2}$
$=x^{2}-2xy+y^{2}=(x+y)^{2}$ 

Answer 2

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