document.write( "Question 1177229: Evaluate 3n^2-10n-9, given n(n-3)=28 \n" ); document.write( "
Algebra.Com's Answer #805512 by Theo(13342)\"\" \"About 
You can put this solution on YOUR website!
first you need to solve for n in the equation of n * (n-3) = 28
\n" ); document.write( "simplify this to n^2 - 3n = 28
\n" ); document.write( "subtract 28 from both sides of the equation to get:
\n" ); document.write( "n^2 - 3n - 28 = 0
\n" ); document.write( "solve for n in this quadratic equation to get:
\n" ); document.write( "n = -4 or n = 7.\r
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\n" ); document.write( "\n" ); document.write( "when n = -4, 3n^2 - 10n - 9 = 79.
\n" ); document.write( "when n = 7, 3n^2 - 10n - 9 = 68.\r
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\n" ); document.write( "\n" ); document.write( "those should be your answers.\r
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\n" ); document.write( "\n" ); document.write( "i solved this graphically using the desmos.com calculator.\r
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\n" ); document.write( "\n" ); document.write( "this is what the results of that analysis look like.\r
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\n" ); document.write( "\n" ); document.write( "in the graph, i used x instead of n.\r
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