document.write( "Question 681992: it says, \"Sketch the graphs, using the function and three points: two roots and the turning point.\r
\n" ); document.write( "\n" ); document.write( "f(x)= x^2-2x-8\r
\n" ); document.write( "\n" ); document.write( "f(x)= x^2-2x-15
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Algebra.Com's Answer #422938 by MathLover1(20850)\"\" \"About 
You can put this solution on YOUR website!
1.\r
\n" ); document.write( "\n" ); document.write( "\"f%28x%29=+x%5E2-2x-8\"...factor completely, replace \"-2x\" with \"2x-4x\"\r
\n" ); document.write( "\n" ); document.write( "\"f%28x%29=+x%5E2%2B2x-4x-8\".......group\r
\n" ); document.write( "\n" ); document.write( "\"f%28x%29=+%28x%5E2%2B2x%29-%284x%2B8%29\"\r
\n" ); document.write( "\n" ); document.write( "\"f%28x%29=+x%28x%2B2%29-4%28x%2B2%29\"\r
\n" ); document.write( "\n" ); document.write( "\"f%28x%29=+%28x-4%29%28x%2B2%29\"....set \"f%28x%29=0\"\r
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\n" ); document.write( "\n" ); document.write( "\"0=+%28x-4%29%28x%2B2%29\"\r
\n" ); document.write( "\n" ); document.write( "if \"0=+%28x-4%29\"..=>...\"x=4\"\r
\n" ); document.write( "\n" ); document.write( "if \"0=+%28x%2B4%29\"..=>...\"x=-2\"\r
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\n" ); document.write( "\n" ); document.write( "so, the roots are \"x=4\" and \"x=-2\"\r
\n" ); document.write( "\n" ); document.write( "and points are (\"4\",\"0\") and (\"-2\",\"0\")\r
\n" ); document.write( "\n" ); document.write( "let \"x=1\", solve for \"f%28x%29\" and find third point\r
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\n" ); document.write( "\n" ); document.write( "\"f%281%29=+1%5E2-2%2A1-8\"\r
\n" ); document.write( "\n" ); document.write( "\"f%281%29=+1-2-8\"\r
\n" ); document.write( "\n" ); document.write( "\"f%281%29=+-9\"\r
\n" ); document.write( "\n" ); document.write( "so, third point is (\"1\",\"-9\")\r
\n" ); document.write( "\n" ); document.write( "now, graph it\r
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\n" ); document.write( "\n" ); document.write( "2.\r
\n" ); document.write( "\n" ); document.write( "\"f%28x%29=++x%5E2-2x-15\"...factor completely, replace \"-2x\" with \"3x-5x\"\r
\n" ); document.write( "\n" ); document.write( "\"f%28x%29=+x%5E2%2B3x-5x-15\".......group\r
\n" ); document.write( "\n" ); document.write( "\"f%28x%29=+%28x%5E2%2B3x%29-%285x%2B15%29\"\r
\n" ); document.write( "\n" ); document.write( "\"f%28x%29=+x%28x%2B3%29-5%28x%2B3%29\"\r
\n" ); document.write( "\n" ); document.write( "\"f%28x%29=+%28x-5%29%28x%2B3%29\"....set \"f%28x%29=0\"\r
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\n" ); document.write( "\n" ); document.write( "\"0=+%28x-5%29%28x%2B3%29\"\r
\n" ); document.write( "\n" ); document.write( "if \"0=+%28x-5%29\"..=>...\"x=5\"\r
\n" ); document.write( "\n" ); document.write( "if \"0=+%28x%2B3%29\"..=>...\"x=-3\"\r
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\n" ); document.write( "\n" ); document.write( "so, the roots are \"x=5\" and \"x=-3\"\r
\n" ); document.write( "\n" ); document.write( "and points are (\"5\",\"0\") and (\"-3\",\"0\")\r
\n" ); document.write( "\n" ); document.write( "let \"x=1\", solve for \"f%28x%29\" and find third point\r
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\n" ); document.write( "\n" ); document.write( "\"f%281%29=+1%5E2-2%2A1-15\"\r
\n" ); document.write( "\n" ); document.write( "\"f%281%29=+1-2-15\"\r
\n" ); document.write( "\n" ); document.write( "\"f%281%29=+-16\"\r
\n" ); document.write( "\n" ); document.write( "so, third point is (\"1\",\"-16\")\r
\n" ); document.write( "\n" ); document.write( "now, graph it\r
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