document.write( "Question 253390: how do the graphs of f(x)=x^2 + x and g(x)= x^2+|x| compare?
\n" ); document.write( "A. f(x)=g(x) for x<0
\n" ); document.write( "B. f(x)>g(x) for x<0
\n" ); document.write( "C. f(x)=g(x) for x> or equal to 0
\n" ); document.write( "D. f(x)> g(x) for x> or equal to 0
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Algebra.Com's Answer #185739 by Theo(13342)\"\" \"About 
You can put this solution on YOUR website!
I would say selection c.\r
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\n" ); document.write( "\n" ); document.write( "when x < 0, f(x) < g(x) so selection a is false.
\n" ); document.write( "when x < 0, f(x) < g(x) so selection b is false.
\n" ); document.write( "when x >= 0 f(x) = g(x) so selection c looks good since |x| = x when x >= 0
\n" ); document.write( "when x >= 0 f(x) = g(x) so selection d is false.\r
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\n" ); document.write( "\n" ); document.write( "graph of both equations looks like this:\r
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\n" ); document.write( "\n" ); document.write( "\"graph+%28600%2C600%2C-10%2C10%2C-10%2C200%2Cx%5E2+%2B+x%2Cx%5E2+%2B+abs%28x%29%2C56%2C72%29\"\r
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\n" ); document.write( "\n" ); document.write( "you can see that when x >= 0 it looks like one graph.\r
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\n" ); document.write( "\n" ); document.write( "this is because the 2 equations are identical and become superimposed on each other.\r
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\n" ); document.write( "\n" ); document.write( "when x is negative, the graphs are separate.\r
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\n" ); document.write( "\n" ); document.write( "the red graph (the lower one) is the equation f(x) = x^2 + x. \r
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\n" ); document.write( "\n" ); document.write( "the green graph (the higher one) is the equation f(x) = x^2 + |x|\r
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\n" ); document.write( "\n" ); document.write( "as an example:\r
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\n" ); document.write( "\n" ); document.write( "when x = -8, x^2 + x becomes 64 - 8 = 56\r
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\n" ); document.write( "\n" ); document.write( "when x = -8 x^2 + |x| becomes 64 + 8 = 72\r
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\n" ); document.write( "\n" ); document.write( "I drew horizontal lines at y = 56 and y = 72 so you could see that easier.\r
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\n" ); document.write( "\n" ); document.write( "find x = -8 and trace vertically up until you see the intersection points.\r
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