\"\"

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The side lengths of a right triangle are \"\" ; \"a

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Apply Pythagorean theorem: \"a

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\"\"                    (Substitute 2 for b and 5 for c)

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\"\"                     (Evaluate powers: \"\")\"\"

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\"\"         (Subtract 49 from each side)

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\"\"               (Apply additive inverse property: \"\")

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\"\"                     (Apply additive identity property: \"\")

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\"\"                           (Subtract: \"\")

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 \"\"                   (Take square root to each side)

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\"\"                         (Cancel square and root)\"\"

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The unknown length of \"\"ft.