document.write( "Question 1125335: Find two positive numbers satisfying the given requirements.
\n" ); document.write( "The sum of the first and twice the second is 120 and the product is a maximum.
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Algebra.Com's Answer #741649 by greenestamps(13200)\"\" \"About 
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\n" ); document.write( "Let the numbers be x and y. Then we know

\n" ); document.write( "\"x%2B2y=120\"
\n" ); document.write( "\"2y+=+120-x\"
\n" ); document.write( "\"y+=+60-x%2F2\"

\n" ); document.write( "So the second number is 60-x/2.

\n" ); document.write( "We want the product of the two numbers to be a maximum. The product is

\n" ); document.write( "\"x%2860-x%2F2%29+=+-%281%2F2%29x%5E2%2B60x\"

\n" ); document.write( "The maximum/minimum value of the quadratic expression ax^2+bx+c is when x = -b/2a. In this problem, that is

\n" ); document.write( "\"-60%2F-1+=+60\"

\n" ); document.write( "So the first number is 60 and the second is 60-30 = 30. The product is 1800.
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