document.write( "Question 1006087: The sum of the cube of a number and twelve times the number is equal to 7 times the square of the number. Find the number \n" ); document.write( "
Algebra.Com's Answer #622233 by Theo(13342)\"\" \"About 
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let x = the number.\r
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\n" ); document.write( "\n" ); document.write( "the cube of the number becomes x^3\r
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\n" ); document.write( "\n" ); document.write( "12 times the number becomes 12x\r
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\n" ); document.write( "\n" ); document.write( "7 time the square of the number becomes 7x^2\r
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\n" ); document.write( "\n" ); document.write( "you get:\r
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\n" ); document.write( "\n" ); document.write( "x^3 + 12x = 7x^2\r
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\n" ); document.write( "\n" ); document.write( "subtract 7x^2 from both sides of the equation to get:\r
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\n" ); document.write( "\n" ); document.write( "x^3 - 7x^2 + 12x = 0\r
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\n" ); document.write( "\n" ); document.write( "factor out an x to get:\r
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\n" ); document.write( "\n" ); document.write( "x * (x^2 - 7x + 12) = 0\r
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\n" ); document.write( "\n" ); document.write( "factor the quadratic to get:\r
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\n" ); document.write( "\n" ); document.write( "x * (x-4) * (x-3) = 0\r
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\n" ); document.write( "\n" ); document.write( "set each of the factors equal to 0 and solve for x to get:\r
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\n" ); document.write( "\n" ); document.write( "x = 0
\n" ); document.write( "x = 4
\n" ); document.write( "x = 3\r
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\n" ); document.write( "\n" ); document.write( "those are the values of x that makes the original equation true.\r
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\n" ); document.write( "\n" ); document.write( "the original equation is:\r
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\n" ); document.write( "\n" ); document.write( "x^3 + 12x = 7x^2\r
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\n" ); document.write( "\n" ); document.write( "when x = 0, you get 0 = 0 which is true.\r
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\n" ); document.write( "\n" ); document.write( "when x = 3, you get 63 = 63 which is true.\r
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\n" ); document.write( "\n" ); document.write( "when x = 4, you get 112 = 112 which is true.\r
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\n" ); document.write( "\n" ); document.write( "you have 3 possible values of x that satisfy the constraints of the problem.\r
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\n" ); document.write( "\n" ); document.write( "they are x = 0,3,4\r
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