document.write( "Question 1153918: The graph of a parabola passes through the points (3/2, 4/3) and (0, −6) and
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Algebra.Com's Answer #776243 by ikleyn(52800)\"\" \"About 
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document.write( "Since the parabola has a horizontal tangent line at the point (3/2,4/3), it means \r\n" );
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document.write( "that this point (3/2,4/3) is the vertex of the parabola.\r\n" );
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document.write( "Hence, the parabola has the form\r\n" );
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document.write( "    y(x) = \"a%2A%28x-3%2F2%29%5E2+%2B+4%2F3\",\r\n" );
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document.write( "where \"a\" is a coefficient (real number), now unknown.\r\n" );
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document.write( "To find \"a\", use the fact that the plot of the parabola passes through the point (0,-6). It means that\r\n" );
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document.write( "    y(0) = -6,   or   \"a%2A%280+-+3%2F2%29%5E2+%2B+4%2F3\" = -6,   or\r\n" );
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document.write( "    \"a%2A%283%2F2%29%5E2+%2B+4%2F3\" = -6.\r\n" );
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document.write( "It gives\r\n" );
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document.write( "    \"a%2A%289%2F4%29\" = \"-6+-+4%2F3\" = \"%28-18-4%29%2F3\" = \"-22%2F3\",\r\n" );
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document.write( "hence\r\n" );
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document.write( "    a = \"%284%2F9%29%2A%28-22%2F3%29\" = \"-88%2F27\".\r\n" );
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document.write( "Thus the equation of the parabola is  \r\n" );
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document.write( "    y(x) = \"%28-88%2F27%29%2A%28x-3%2F2%29%5E2+%2B+4%2F3\".\r\n" );
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document.write( "You can transform it to any other equivalent form you wish.\r\n" );
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document.write( "Regarding the plot, do it on your own.\r\n" );
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document.write( "You may use free of charge plotting tools from the Internet.\r\n" );
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