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Algebra Difficulty 1.4 Junior Find the answer Canada

If $x=2y$ and $y \neq 0$ , then $(x-y)(2x+y)$ equals

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Solution

Since $x=2y$ , then $(x-y)(2x+y)=(2y-y)(2(2y)+y)=(y)(5y) = 5y^2$ .

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Source: CEMC, University of Waterloo, licensed CC-BY-NC-4.0. Statement reproduced verbatim; metadata (topic, difficulty) added by this project.