document.write( "Question 903107: In a math book I am using / reading the author states that the expression n + (n-3) simplifies to n(n-1). But he does not show steps for this or give an explanation.\r
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document.write( "I checked the expression on many web-based math sites (including your site) and none show the simplification of the original expression as n(n-1).\r
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document.write( "One site states that n + (n-3) simplifies to the following expression (with steps shown):
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document.write( "Simplifying
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document.write( "n + n(n + -3)\r
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document.write( "Reorder the terms:
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document.write( "n + n(-3 + n)
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document.write( "n + (-3 * n + n * n)
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document.write( "n + (-3n + n2)\r
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document.write( "Combine like terms: n + -3n = -2n
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document.write( "-2n + n2
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document.write( "Can you state whether the expression n + n(n-3) can simplify to n(n-1) and if so, can you please show the steps.\r
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document.write( "Thank you in advance.\r
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document.write( "Greg \n" );
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Algebra.Com's Answer #547796 by AlgebraLady88(44)![]() ![]() You can put this solution on YOUR website! Ok, let's take a look at the equation\r \n" ); document.write( "\n" ); document.write( "n + n (n- 3)\r \n" ); document.write( "\n" ); document.write( "For the part n (n +3) , we can express this using the Distributive Postulate. A postulate is a statement that is true. The Distributive method is as follows:\r \n" ); document.write( "\n" ); document.write( "a (b + c) = ab + ac\r \n" ); document.write( "\n" ); document.write( "We take the 'a' and multiply it with the 'b' which gives us ab plus the 'a' multiplied by the 'c,' which gives us ac\r \n" ); document.write( "\n" ); document.write( "So, n + n ( n-3) = n + n ^ 2 - 3n = n^2 - 2n = n (n -2)\r \n" ); document.write( "\n" ); document.write( "It will not simplify to n (n-1) . \r \n" ); document.write( "\n" ); document.write( "\" One item I should have asked about this expression. If the simplified expression n(n-2) is put over denominator of 2, would this then simplify to n(n-1) ??\"\r \n" ); document.write( "\n" ); document.write( "The answer is no. Here's why. You can only cancel factors , not terms in a polynomial. Let me explain .\r \n" ); document.write( "\n" ); document.write( "2n/2 * n/2 = n^2/2 Correct \r \n" ); document.write( "\n" ); document.write( "(2n + 5)/ 2 = n + 5 Incorrect ( You cannot cancel the 2's and get n+5)\r \n" ); document.write( "\n" ); document.write( "So, for [n(n-2)]/2 , your answer would still be [n(n-2])/2 because there are no factors to cancel.\r \n" ); document.write( "\n" ); document.write( "You can alternately do this:\r \n" ); document.write( "\n" ); document.write( "[n(n-2)]/2 = (n^2-2n)/2= n^2/2 -2n/2 = n^2/2 - n \r \n" ); document.write( "\n" ); document.write( "You are getting rid of the parenthesis and then putting each term over the same denominator. The two terms are n^2 and -2n . You put each over the denominator 2. Then you can reduce each separate fraction where applicable.However, it does make things more complicated. This topic comes under \n" ); document.write( "'simplifying rational expressions.\"\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |