document.write( "Question 945507: How would I simplify this expression (10-√5 )(10+√5)? \n" ); document.write( "

Algebra.Com's Answer #576694 by KMST(5328) $\"\"$ $\"About$

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Simple is a relative term.
\n" ); document.write( "What a math teacher would want you to do is rationalize.
\n" ); document.write( "Rationalize means convert that expression into an equivalent expression that does not have any irrational number (square root or the like) in the denominator.
\n" ); document.write( "To do that you use the \"conjugate\" of the denominator,
\n" ); document.write( "a factor that multiplied times the denominator gives ypu a nice rational number.
\n" ); document.write( "Since $\"%2810%2Bsqrt%285%29%29%2A%2810-sqrt%285%29%29=10%5E2-%28sqrt%285%29%29%5E2=100-5=95\"$ ,
\n" ); document.write( "you multiply numerator and denominator times $\"%2810-sqrt%285%29%29\"$ .
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