The answer is: " 13√7 " .
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Step-by-step explanation:
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" √63 " = √9 √7 = " 3√7 " .
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" √28 " = √4 √7 = " 2√7 " .
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" 5√28 " = " 5 * 2 * √7 = " 10√7 " .
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→ " 5√28 " + " √63 " ;
= " 10√7 " + " 3√7 " ;
= " (10 + 3) * (√7) " ;
= " 13 √ 7 "
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The answer is: " 13√7 " .
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