document.write( "Question 136648This question is from textbook Algebra Structure and Method
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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" );
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Algebra.Com's Answer #100087 by ankor@dixie-net.com(22740)![]() ![]() You can put this solution on YOUR website! 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( " \n" ); document.write( ": \n" ); document.write( " \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( " \n" ); document.write( ": \n" ); document.write( "Actually the negative solution x = -9 will work also: \n" ); document.write( " \n" ); document.write( ": \n" ); document.write( ": \n" ); document.write( "Did I make this understandable? Any questions? \n" ); document.write( " |