document.write( "Question 366606: I just solved a problem on my algebra test, and I am not sure how I did it... In regards to a rectangle with sides X and 2x+5, and area being 168\r
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\n" ); document.write( "\n" ); document.write( "While trying to work on it, I was factoring 168, and realized the factors 8,21 fit for X and 2x+5... it was an intuitive leap. I would like to know how to actually solve this properly \n" ); document.write( "

Algebra.Com's Answer #261278 by ewatrrr(24785) $\"\"$ $\"About$

You can put this solution on YOUR website!


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document.write( "Hi, 
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document.write( "x(2x+5)=168 
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document.write( "2x^2 + 5x - 168 = 0
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document.write( "Yes, factoring works: 
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document.write( "Coming up with the product of -8*21 = 168 and using that
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document.write( "(2x +21)(x -8) = 0  
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document.write( "(2x + 21)=0
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document.write( "x = -(21/10) = -10.5
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document.write( "(x -8) = 0 
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document.write( "x = 8 
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document.write( "The quadratic equations \"always\" works as well:
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document.write( "x = (-5 + 37)/4 = 8
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document.write( "x = (-5 -37)/4 = -42/4 = -21/2 = -10.5\r
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