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Simplify

Algebra Level 2

Simplify \(\dfrac{3^x+63}{21^{x-2}+7^{x-1}}\).

\[\dfrac{3}{7^x}\] \[\dfrac{9}{7^x}\] \[\dfrac{3\times7}{7^x}\] \[\dfrac{9\times49}{7^x}\] \[\dfrac{9\times7}{7^x}\]

Excel in math and science

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It's hard to learn from lectures and videos

Learn more effectively through short, conceptual quizzes.

Our wiki is made for math and science

Master advanced concepts through explanations,
examples, and problems from the community.

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including olympiad champions, researchers, and professionals.

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by Khang Nguyen Thanh

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