document.write( "Question 136648This question is from textbook Algebra Structure and Method
\n" ); document.write( ": The numerator of a fraction is 1 less than the denominator. If the numerator and the denominator are both increased by 4, the new fraction will be 1/8 more than the original fraction. Find the original fraction. \n" ); document.write( "
Algebra.Com's Answer #100087 by ankor@dixie-net.com(22740)\"\" \"About 
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The numerator of a fraction is 1 less than the denominator. If the numerator and the denominator are both increased by 4, the new fraction will be 1/8 more than the original fraction. Find the original fraction.
\n" ); document.write( ":
\n" ); document.write( "Write an equation for what it says:
\n" ); document.write( "\"x%2F%28%28x%2B1%29%29\" + \"1%2F8\" = \"%28%28x%2B4%29%29%2F%28%28x%2B1%2B4%29%29\"
\n" ); document.write( ":
\n" ); document.write( "\"x%2F%28%28x%2B1%29%29\" + \"1%2F8\" = \"%28%28x%2B4%29%29%2F%28%28x%2B5%29%29\"
\n" ); document.write( ":
\n" ); document.write( "The common denominator will be 8(x+1)(x+5)
\n" ); document.write( "Multiply each term by this, cancel out the denominators, leaving us with:
\n" ); document.write( "x(8(x+5) + (x+1)(x+5) = 8(x+4)(x+1)
\n" ); document.write( ":
\n" ); document.write( "8x^2 + 40x + x^2 + 6x + 5 = 8(x^2 + 5x + 4)
\n" ); document.write( ":
\n" ); document.write( "8x^2 + 40x + x^2 + 6x + 5 = 8x^2 + 40x + 32
\n" ); document.write( "Combine on the left:
\n" ); document.write( "8x^2 + x^2 - 8x^2 + 40x + 6x - 40x + 5 - 32 = 0
\n" ); document.write( "A quadratic equation
\n" ); document.write( "x^2 + 6x - 27 = 0
\n" ); document.write( "Factors to:
\n" ); document.write( "(x+9)(x-3) = 0
\n" ); document.write( "We want the positive solution:
\n" ); document.write( "x = 3
\n" ); document.write( ":
\n" ); document.write( "Check solution in original equation
\n" ); document.write( "\"3%2F%28%284%29%29\" + \"1%2F8\" = \"%28%287%29%29%2F%28%288%29%29\"
\n" ); document.write( ":
\n" ); document.write( "Actually the negative solution x = -9 will work also:
\n" ); document.write( "\"%28-9%29%2F%28%28-8%29%29\" + \"1%2F8\" = \"%28%28-5%29%29%2F%28%28-5%29%29\"
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\n" ); document.write( "Did I make this understandable? Any questions?
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