document.write( "Question 1138954: Find two numbers whose sum is
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\n" ); document.write( "\n" ); document.write( "What two numbers yield this​ product?
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Algebra.Com's Answer #756727 by rothauserc(4718)\"\" \"About 
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let x, y be the two numbers
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\n" ); document.write( "x + y = 28
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\n" ); document.write( "if the two numbers are 1 and 27, then
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\n" ); document.write( "1) x + y = 28
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\n" ); document.write( "2) xy = 27
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\n" ); document.write( "solve equation 1 for y, then substitute for y in equation 2
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\n" ); document.write( "3) y = 28 -x
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\n" ); document.write( "x(28-x) = 27
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\n" ); document.write( "4) -x^2 +28x -27 = 0
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\n" ); document.write( "the graph of equation 4 is a parabola that curves downward, so the coordinates of the vertex is the maximum values for x and y
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\n" ); document.write( "x coordinate = -b/2a = -28/2(-1) = 14
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\n" ); document.write( "substitute for x in equation 3
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\n" ); document.write( "y = 28 -14 = 14
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\n" ); document.write( "the maximum product occurs when x=14 and y=14
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\n" ); document.write( "Note 14 * 14 = 196
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