document.write( "Question 288382: write √45 in the form k√5, where k is an integer \n" ); document.write( "
Algebra.Com's Answer #209034 by jim_thompson5910(35256)\"\" \"About 
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Solved by pluggable solver: Simplifying Square Roots (whole numbers only)
\"sqrt%2845%29\" Start with the given expression
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\n" ); document.write( " The goal of simplifying expressions with square roots is to factor the radicand into a product of two numbers. One of these two numbers must be a perfect square. When you take the square root of this perfect square, you will get a rational number.
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\n" ); document.write( " So let's list the factors of 45
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\n" ); document.write( " Factors:
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\n" ); document.write( " 1, 3, 5, 9, 15, 45
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\n" ); document.write( " Notice how 9 is the largest perfect square, so lets factor 45 into 9*5
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\n" ); document.write( " \"sqrt%289%2A5%29\" Factor 45 into 9*5
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\n" ); document.write( " \"sqrt%289%29%2Asqrt%285%29\" Break up the square roots using the identity \"sqrt%28x%2Ay%29=sqrt%28x%29%2Asqrt%28y%29\"
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\n" ); document.write( " \"3%2Asqrt%285%29\" Take the square root of the perfect square 9 to get 3
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\n" ); document.write( " So the expression \"sqrt%2845%29\" simplifies to \"3%2Asqrt%285%29\"
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\n" ); document.write( " ----------------------------
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\n" ); document.write( " Notice if we evaluate the square root of 45 with a calculator we get
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\n" ); document.write( " \"sqrt%2845%29=6.70820393249937\"
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\n" ); document.write( " and if we evaluate \"3%2Asqrt%285%29\" we get
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\n" ); document.write( " \"3%2Asqrt%285%29=6.70820393249937\"
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\n" ); document.write( " This shows that \"sqrt%2845%29=3%2Asqrt%285%29\". So this verifies our answer

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\n" ); document.write( "\n" ); document.write( "Since \"sqrt%2845%29=3%2Asqrt%285%29\", this means that \"k=3\"
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