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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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by Khang Nguyen Thanh

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