document.write( "Question 1177574: Find the relationship between p and q, if the equation px² + 3qx + 9 = 0 has equal roots. \n" ); document.write( "

Algebra.Com's Answer #806632 by Edwin McCravy(20056) $\"\"$ $\"About$

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document.write( "Divide through by p\r\n" );
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document.write( "The sum of the roots is the coefficient of x with the opposite sign, -3q/p.\r\n" );
document.write( "Since the roots are equal, let them be r and r.\r\n" );
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document.write( "The product of the roots is the constant term 9/p.\r\n" );
document.write( "Since the roots are both r, their product is r².\r\n" );
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document.write( "So we have a system of equations to solve\r\n" );
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document.write( "Solve the first for r\r\n" );
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document.write( "Substitute in the 2nd equation in the system:\r\n" );
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document.write( "Cross-multiply:\r\n" );
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document.write( "p cannot be 0, so we may divide both sides by it\r\n" );
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document.write( "Edwin

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