document.write( "Question 1002047: The sum of the lengths of the two perpendicular sides of a right triangle is 30 centimeters. What are their lengths if the square of the hypotenuse is a minimum? \n" ); document.write( "
Algebra.Com's Answer #619063 by josgarithmetic(39617)\"\" \"About 
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h, hypotenuse
\n" ); document.write( "x and 30-x are lengths of the legs.
\n" ); document.write( "\"h%5E2=x%5E2%2B%2830-x%29%5E2\"
\n" ); document.write( "\"h%5E2=x%5E2%2B30%5E2-60x%2Bx%5E2\"
\n" ); document.write( "\"h%5E2=2x%5E2-60x%2B900\"\r
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\n" ); document.write( "\n" ); document.write( "Find the x value or values for the minimum \"h%5E2\".
\n" ); document.write( "\"2x%5E2-60x%2B900=0\"
\n" ); document.write( "\"x%5E2-30x%2B450=0\"
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\n" ); document.write( "Discriminant, \"900-4%2A450=NegativeNumber\"
\n" ); document.write( "This method, finding the roots, will not work here because \"h%5E2\" as a function does not intersect the x-axis.\r
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\n" ); document.write( "\n" ); document.write( "You can complete the square for making into standard form, and then read the vertex (a minimum point) from that form of the equation. The term to use is \"%2830%2F2%29%5E2=15%5E2\", or 225.\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2-30x%2B15%5E2%2B450-225=0\"
\n" ); document.write( "\"%28x-15%29%5E2%2B225=0\"
\n" ); document.write( "Showing x=15 for the vertex, and then one leg of the triangle is 15, and therefore the other leg is \"30-x=30-15=15\" also.
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