document.write( "Question 177739: you are given a cube. the length, width, and height = x. if the length is increased by 12, the width is increased by 6, and the height is decreased by 4 than the volume doubles. find x. \n" ); document.write( "
Algebra.Com's Answer #132760 by Mathtut(3670)\"\" \"About 
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\"A=x%5E3\"....eq 1
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\n" ); document.write( "\"%28x%2B12%29%28x%2B6%29%28x-4%29=2A\"...eq 2
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\n" ); document.write( "take value of A from eq 1 and plug it into eq 2
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\n" ); document.write( "\"%28x%2B12%29%28x%2B6%29%28x-4%29=2x%5E3\"
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\n" ); document.write( "\"%28x%5E2%2B18x%2B72%29%28x-4%29=2x%5E3\"
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\n" ); document.write( "\"x%5E3-4x%5E2%2B18x%5E2-72x%2B72x-288=2x%5E3\"
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\n" ); document.write( "\"x%5E3-14x%5E2%2B288=0\"\r
\n" ); document.write( "\n" ); document.write( "if we take the factors of plus or minus 288/1 we have possible rational roots
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\n" ); document.write( "if you plug 6 in you will find that to be a factor so lets use synthetic division to factor 6 out of our equation
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\n" ); document.write( " l 1 -14 0 288
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\n" ); document.write( "6 l____ 6___-48___-288____________________________
\n" ); document.write( " 1 -8 -48 0\r
\n" ); document.write( "\n" ); document.write( "so we have (x-6)(x^2-8x-48)
\n" ); document.write( "which can be further factored to (x-6)(x-12)(x+4)
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\n" ); document.write( "so x is 6,12,0r -4..since 4 is negative we throw it out
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\n" ); document.write( "\"system%28x=6%2Cx=12%29\"
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