document.write( "Question 854077: Simplify the rational expression.
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document.write( "(9x^3-41x^2-20x) / (yx^2-2yx-15y) \r
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document.write( "Would you factor it like this?
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document.write( "9x^3-45x^2+4x^2-20x / yx^2+3yx-5yx-15y\r
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document.write( "Thank you for your help!
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Algebra.Com's Answer #514849 by Theo(13342)![]() ![]() You can put this solution on YOUR website! problem is:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Simplify the rational expression. \n" ); document.write( "(9x^3-41x^2-20x) / (yx^2-2yx-15y) \r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "factor out an x in the numerator to get x * (9x^2 - 41x - 20)\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "factor out a y in the denominator to get y * (x^2 - 2x - 15)\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "your expression becomes:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "x * (9x^2 - 41x - 20) / (y * (x^2 - 2x - 15)\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "factor 9x^2 - 41x - 20 in the numerator to get x * (9x + 4) * (x - 5)\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "factor x^2 - 2x - 15 in the denominator to get y * (x - 5) * (x + 3)\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "your expression becomes:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "[x * (9x + 4) * (x = 5)] / [y * (x - 5) * (x + 3)]\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "the (x-5) in the numerator cancels out the (x-5) in the denominator and you are left with:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "(x * (9x + 4)] / [y * (x + 3)]\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "if you simplify this, you will get:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "(9x^2 + 4x) / (yx + 3y)\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "that should be it.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "there are many different ways to factor a quadratic.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "you last resort, if you can't do it any other way, is the quadratic formula.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "that formula is x = [-b +/- sqrt(b^2 - 4ac)] / 2a\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "once you find the roots, you then need to set the root equal to 0 in order to find the factor.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "for example:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "the factor of 9x + 4 creates the root of x = -4/9.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "the quadratic formula will give you that root, but it will not give you the factor that created that root.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "to find the factor you would do the following:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "start with x = -4/9 \n" ); document.write( "multiply both sides of this equation by 9 to get: \n" ); document.write( "9x = -4 \n" ); document.write( "add 4 to both sides of this equation to get 9x + 4 = 0 \n" ); document.write( "9x + 4 is the factor.\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |