document.write( "Question 158074: 18x/x^2-5x-36 + 2x/x+4\r
\n" ); document.write( "\n" ); document.write( "I am not sure how to add rational equations. I was told to take the number that is largest and use it as the common denominator. Does the largest number have to have a variable with it? Please show me how to work this out. Thanks so much! \n" ); document.write( "

Algebra.Com's Answer #116462 by Earlsdon(6294) $\"\"$ $\"About$

You can put this solution on YOUR website!
Simplify:
\n" ); document.write( " $\"%2818x%2F%28x%5E2-5x-36%29%29%2B%282x%2F%28x%2B4%29%29\"$ Did I get this right? If so, then factor the denominator of the first fraction.
\n" ); document.write( " $\"%2818x%2F%28x%2B4%29%28x-9%29%29%2B%282x%2F%28x%2B4%29%29\"$ The common denominator is $\"%28%28x%2B4%29%29%28%28x-9%29%29\"$ so multiply the second fraction by: $\"%28x-9%29%2F%28x-9%29\"$ to get:
\n" ); document.write( " $\"%2818x%2F%28x%2B4%29%28x-9%29%29%2B%282x%28x-9%29%2F%28x%2B4%29%28x-9%29%29\"$ Perform the indicated addition.
\n" ); document.write( " $\"%2818x%2B2x%28x-9%29%29%2F%28x%2B4%29%28x-9%29\"$ Simplify.
\n" ); document.write( " $\"highlight%282x%5E2%2F%28x%5E2-5x-36%29%29\"$ \n" ); document.write( "

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