The answer is: [A]: " 3 √2 " .
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Solve for "s" ;
s² + s² = 6² ;
2s² = 36 ;
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Divide EACH side of the equation by "2" ;
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2s² / 2 = 36 / 2 ;
to get:
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s² = 18 ;
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Take the positive square root of EACH side:
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√(s²) = √(18)
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s = √(18) = √9 * √2 = 3 √2 ; which is: Answer choice: [A].
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