document.write( "Question 1177572: The equation x²+ px +4 = 0, where p and q are constants, has roots -1 and 4. a) Find the values of p and q.\r
\n" ); document.write( "\n" ); document.write( "b) Using these values of p and q. find the value of r, where r is a constant, and the equation x² + px + r=0 has equal roots.
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Algebra.Com's Answer #806642 by MathLover1(20850)\"\" \"About 
You can put this solution on YOUR website!
\"q\" is missing from given equation, so I assume you have\"+x%5E2%2B+px+%2B4q+=+0\"\r
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\n" ); document.write( "\n" ); document.write( "a) Find the values of \"p\" and \"q\".\r
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\n" ); document.write( "\n" ); document.write( "use the rule: sum of the roots = \"-b%2Fa+\"
\n" ); document.write( "roots are \"-1\" and \"4\", sum is \"-1%2B4=3\"\r
\n" ); document.write( "\n" ); document.write( "\"-b%2Fa+=3\".........\"b=p\", \"a=1\"
\n" ); document.write( "\"-p%2F1+=3\"
\n" ); document.write( "\"p=-3\"\r
\n" ); document.write( "\n" ); document.write( "and \r
\n" ); document.write( "\n" ); document.write( "product of the roots =\"+c%2Fa\"\r
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\n" ); document.write( "\n" ); document.write( "\"c=4q\", \"a=1\"\r
\n" ); document.write( "\n" ); document.write( "\"4q%2F1=%28-1%29%2A4\"\r
\n" ); document.write( "\n" ); document.write( "\"4q=-4\"\r
\n" ); document.write( "\n" ); document.write( "\"q=-1\"\r
\n" ); document.write( "\n" ); document.write( "\"+x%5E2-3x+-4+=+0\"\r
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\n" ); document.write( "\n" ); document.write( "b) Using these values of \"p+\"and \"q\" find the value of \"r\", where \"r\" is a constant, and the equation
\n" ); document.write( "\"x%5E2%2B+px+%2B+r=0\" has \"equal\" roots \r
\n" ); document.write( "\n" ); document.write( "\"p=-3\"\r
\n" ); document.write( "\n" ); document.write( "\"x%5E2-3x+%2B+r=0\".....if equation has \"equal\" roots, write left side as square of difference
\n" ); document.write( "sum of the roots \"-b%2Fa+=-%28-3%29%2F1+=3\"\r
\n" ); document.write( "\n" ); document.write( "\"x%5B1%5D%2Bx%5B2%5D=3\"..............eq.1. since \"x%5E2%2B+px+%2B+r=0\" has \"equal\" roots, \"x%5B1%5D=x%5B2%5D\"\r
\n" ); document.write( "\n" ); document.write( "\"2x%5B1%5D=3\"
\n" ); document.write( "\"x%5B1%5D=3%2F2\"\r
\n" ); document.write( "\n" ); document.write( "product of the roots =\"+c%2Fa=r%2F1=r\" \r
\n" ); document.write( "\n" ); document.write( "\"x%5B1%5D%2Ax%5B1%5D=r\"..............eq.2
\n" ); document.write( "\"%283%2F2%29%2A%283%2F2%29=r\"
\n" ); document.write( "\"r=9%2F4\"\r
\n" ); document.write( "\n" ); document.write( "and your equatio is:\r
\n" ); document.write( "\n" ); document.write( "\"x%5E2-3x+%2B+9%2F4=0\"\r
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