document.write( "Question 572140: 14/(x+4)=5-x \n" ); document.write( "
Algebra.Com's Answer #368664 by mathsmiles(68)\"\" \"About 
You can put this solution on YOUR website!
14/(x+4)=5-x\r
\n" ); document.write( "\n" ); document.write( "The first thing I'd do is get rid of the (x+4) so we don't have a fraction anymore
\n" ); document.write( "Do that by multiplying both sides by (x+4) giving ... \r
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\n" ); document.write( "\n" ); document.write( "14 = (5-x)(x+4) Now multiply out the parens using FOIL ...
\n" ); document.write( "14 = 5x + 20 - x^2 - 4x Rearranging the terms ...
\n" ); document.write( "14 = -x^2 + 5x - 4x + 20 Now combine the x terms ...
\n" ); document.write( "14 = -x^2 + x + 20 Now let's get all the factors on one side of the equation so we can solve. Subtract 14 from both sides ...
\n" ); document.write( "-x^2 + x + 6 = 0 I like to make the x^2 term positive, so let's multiply by (-1)
\n" ); document.write( "(-1)(-x^2 + x + 6) = 0
\n" ); document.write( "x^2 - x - 6 = 0\r
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\n" ); document.write( "\n" ); document.write( "Now we need to factor into two multipliers:
\n" ); document.write( "(x _ _)(x _ _) = 0 where each _ represents something we need to figure out, both the operator and the term\r
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\n" ); document.write( "\n" ); document.write( "Since the last term is negative, we know we need one of each + and - operators:
\n" ); document.write( "(x - _)(x + _) = 0\r
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\n" ); document.write( "\n" ); document.write( "Now we need factors of 6 which are different by 1 to get the -x terms:
\n" ); document.write( "Factors of 6:
\n" ); document.write( "6 = 2 * 3 That'll do it!\r
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\n" ); document.write( "\n" ); document.write( "Since we want the middle x term to be negative, let's place 3 in the negative paren giving:
\n" ); document.write( "(x - 3)(x + 2) = 0
\n" ); document.write( "Now we have two possibilities for x:
\n" ); document.write( "x-3 = 0 Adding 3 to each side:
\n" ); document.write( "x = 3
\n" ); document.write( "OR
\n" ); document.write( "x+2 = 0 Adding -2 to each side:
\n" ); document.write( "x = -2\r
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\n" ); document.write( "\n" ); document.write( "Since your problem didn't specify positive or negative, either of these should work. Let's check:
\n" ); document.write( "14/(x+4)=5-x Substituting x=3
\n" ); document.write( "14/(3+4)= 5-3
\n" ); document.write( "14/7 = 5-3
\n" ); document.write( "2 = 2 Correct!\r
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\n" ); document.write( "\n" ); document.write( "14/(x+4) = 5-x Substituting x=-2:
\n" ); document.write( "14/(-2+4) = 5-(-2) Converting the double negative on the right to positive:
\n" ); document.write( "14/(2)=5+2
\n" ); document.write( "14/2 = 7
\n" ); document.write( "7=7 Correct!\r
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