document.write( "Question 935835: This question is from my ACT Math Study book. I'm having trouble understanding the steps to find the answer. \r
\n" ); document.write( "\n" ); document.write( "The Question says:
\n" ); document.write( "Simplify: ((x^2-9)/(x+1)) / ((x+3)/(x^2-1))
\n" ); document.write( "(its written as a fraction divided by the second as a fraction)\r
\n" ); document.write( "\n" ); document.write( "I know the first thing to do is flip the second fraction and then multiply, so I did this and got: (x^2-9)(x^2-1) over (x+1)(x+3). I then FOILed the top and bottom to get: (x^4-10x^2+9) over (x^2 +4x +3). Then I thought I could reduce to: x^4-9x^2+6 over 4x. This answer is wrong. \r
\n" ); document.write( "\n" ); document.write( "The solution in the book is exactly this:
\n" ); document.write( "((x^2-9)/(x+1)) / ((x+3)/(x^2-1)) = ((x+3)(x-3)/(x+1))*((x+1)(x-1)/(x+3))=(x-3)(x-1)=x^2-4x+3. \r
\n" ); document.write( "\n" ); document.write( "I'm not following the steps that the book used to come up with this answer, and am wondering why my approach is incorrect. Thank You for your help!\r
\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "

Algebra.Com's Answer #569169 by MathTherapy(10552) $\"\"$ $\"About$

You can put this solution on YOUR website!

\n" ); document.write( "This question is from my ACT Math Study book. I'm having trouble understanding the steps to find the answer. \r
\n" ); document.write( "\n" ); document.write( "The Question says:
\n" ); document.write( "Simplify: ((x^2-9)/(x+1)) / ((x+3)/(x^2-1))
\n" ); document.write( "(its written as a fraction divided by the second as a fraction)\r
\n" ); document.write( "\n" ); document.write( "I know the first thing to do is flip the second fraction and then multiply, so I did this and got: (x^2-9)(x^2-1) over (x+1)(x+3). I then FOILed the top and bottom to get: (x^4-10x^2+9) over (x^2 +4x +3). Then I thought I could reduce to: x^4-9x^2+6 over 4x. This answer is wrong. \r
\n" ); document.write( "\n" ); document.write( "The solution in the book is exactly this:
\n" ); document.write( "((x^2-9)/(x+1)) / ((x+3)/(x^2-1)) = ((x+3)(x-3)/(x+1))*((x+1)(x-1)/(x+3))=(x-3)(x-1)=x^2-4x+3. \r
\n" ); document.write( "\n" ); document.write( "I'm not following the steps that the book used to come up with this answer, and am wondering why my approach is incorrect. Thank You for your help!
\n" ); document.write( "


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document.write( "The easiest and LEAST confusing way to continue with this is to separate the 2 fractions as follows:
\n" );
document.write( " ÷  ------ I'm sure this looks a lot less confusing now!!
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document.write( " ÷  ----- Factoring  and 
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document.write( " *  ----- Changing DIVISION SYMBOL to MULTIPLICATION, and then INVERTING DIVISOR
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document.write( " *  --- Cancelling numerators and denominators
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document.write( ", or 
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document.write( "You can do the check!! 
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document.write( "Send comments, “thank-yous,” and inquiries to “D” at MathMadEzy@aol.com.
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document.write( "Further help is available, online or in-person, for a fee, obviously. \r
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document.write( "For FREE info and answers to questions about the ASVAB exam, the NYS 3 – 8 city/state wide exams,GENERAL
\n" );
document.write( "MATH and HOMEWORK QUESTIONS, or MATH QUESTIONS related to the Regents Integrated Algebra, 
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document.write( "Regents Geometry, Regents Algebra 2/Trigonometry, SHSAT, COOP/HSPT/TACHS, PSAT, SAT, ACT, SSAT/ISEE,
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document.write( "GRE, CLEP, and the TASC/GED, you can visit: http://asvabstudyzone.freeforums.net/. \n" );
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