document.write( "Question 939556: Find an integer c such that the equation 4x^2+cx=9=0 has a double real root.
\n" ); document.write( "please help me with this problem thank you.
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Algebra.Com's Answer #572562 by MathTherapy(10552)\"\" \"About 
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\n" ); document.write( "Find an integer c such that the equation 4x^2+cx=9=0 has a double real root.
\n" ); document.write( "please help me with this problem thank you.
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\n" ); document.write( "\"4x%5E2+%2B+cx+%2B+9+=+0\" ----- Assuming that the extra “=” sign is actually “+”
\n" ); document.write( "Let c be p to prevent confusion, so the equation now becomes: \"4x%5E2+%2B+px+%2B+9+=+0\"
\n" ); document.write( "For this equation to have a double real root, its discriminant: \"b%5E2+-+4ac\" will equal 0 (zero)
\n" ); document.write( "Therefore, with a being 4; b being p; and c being 9, we get:
\n" ); document.write( "\"p%5E2+-+4%284%29%289%29+=+0\"
\n" ); document.write( "\"p%5E2+-+144+=+0\"
\n" ); document.write( "\"p%5E2+=+144\"
\n" ); document.write( "\"p+=+%22+%22+%2B-sqrt%28144%29\", or p, or \"highlight_green%28c+=+%22+%22+%2B-+12%29\"\r
\n" ); document.write( "\n" ); document.write( "Therefore, in \"4x%5E2+%2B+cx+%2B+9+=+0\", c will have a value of \"%22+%22+%2B-+12\" in order for the equation to have a double root solution. \n" ); document.write( "
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