document.write( "Question 895796: The sum of two numbers is 64. Show that their product has a maximum of 1024. Many thanks \n" ); document.write( "
Algebra.Com's Answer #543013 by josgarithmetic(39617)\"\" \"About 
You can put this solution on YOUR website!
\"x%2By=64\". \"xy%3C=1024\" ?\r
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\n" ); document.write( "\n" ); document.write( "\"y=64-x\".
\n" ); document.write( "\"x%2864-x%29=f\"-----the product of x and y.
\n" ); document.write( "\"f=64x-x%5E2\"
\n" ); document.write( "\"f=-x%5E2%2B64x\"\r
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\n" ); document.write( "\n" ); document.write( "Complete The Square. Use \"%2864%2F2%29%5E2=32%5E2\".
\n" ); document.write( "\"f=-1%28x%5E2-64x%29\"
\n" ); document.write( "\"f=-1%28x%5E2-64x%2B32%5E2-32%5E2%29\"
\n" ); document.write( "\"f=-1%28%28x-32%29%5E2-32%5E2%29\"
\n" ); document.write( "\"highlight_green%28f=-%28x-32%29%5E2%2B32%5E2%29\" ------ standard form, parabolic function.\r
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\n" ); document.write( "\n" ); document.write( "The maximum, the vertex of f is at (32,32^2) and \"32%5E2=1024\".\r
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\n" ); document.write( "\n" ); document.write( "(See my lesson on Completing The Square)
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