document.write( "Question 205851: Solve:\r
\n" ); document.write( "\n" ); document.write( "3(x^2-3x) = 81 \n" ); document.write( "
Algebra.Com's Answer #157653 by algebrapro18(249)\"\" \"About 
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3(x^2-3x) = 81
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\n" ); document.write( "\n" ); document.write( "now we divide both sides by 3 and get
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\n" ); document.write( "\n" ); document.write( "x^2-3x = 27
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\n" ); document.write( "\n" ); document.write( "now subtract 27 from both sides
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\n" ); document.write( "\n" ); document.write( "x^2-3x-27 = 0
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\n" ); document.write( "\n" ); document.write( "now we factor. So what are the factors of -27:
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\n" ); document.write( "\n" ); document.write( "1, 27
\n" ); document.write( "3, 9
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\n" ); document.write( "\n" ); document.write( "hmm so it won't factor...so now we use the quadratic method.
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+\" where a = 1, b = -3, and c -27
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\n" ); document.write( "\n" ); document.write( "so plugging in and simplifying we end up with
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+\"
\n" ); document.write( "\"x+=+%283+%2B-+sqrt%28+9-4%2A1%2A-27+%29%29%2F%282%2A1%29+\"
\n" ); document.write( "\"x+=+%283+%2B-+sqrt%28+9%2B108+%29%29%2F%282%29+\"
\n" ); document.write( "\"x+=+%283+%2B-+sqrt%28+117+%29%29%2F%282%29+\"
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\n" ); document.write( "\n" ); document.write( "Now we know that 117 = 9*13 so the \"%28sqrt%28117%29%29\" = \"%28sqrt%289%2A13%29%29\" and we
\n" ); document.write( "know the square root of 9 is 3 so we can pull that out and we get:
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\n" ); document.write( "\n" ); document.write( "\"x+=+%283+%2B-+3+%2A+sqrt%28+13+%29%29%2F%282%29+\"
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\n" ); document.write( "\n" ); document.write( "which is as simplified as this gets. If your professor wants this in decimal form it comes out to x = 8.4083 and x = -2.4083\r
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