document.write( "Question 107637: find all the values of x satisfying the given conditions
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\n" ); document.write( "y1= --- , ----, ---------, and y1+y2=y3
\n" ); document.write( " x+7 x+3 x^2+10+21\r
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Algebra.Com's Answer #78402 by solver91311(24713)\"\" \"About 
You can put this solution on YOUR website!
Your problem as written doesn't make sense, but I'm going to make an assumption that does and go with that. What I think you meant was:\r
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\n" ); document.write( "\n" ); document.write( "\"y1=1%2F%28x%2B7%29\", \"y2=2%2F%28x%2B3%29\", \"y3=%28-4%29%2F%28x%5E2%2B10x%2B21%29\", and \"y1%2By2=y3\"\r
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\n" ); document.write( "\n" ); document.write( "That means we can say:\r
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\n" ); document.write( "\n" ); document.write( "\"%281%2F%28x%2B7%29%29%2B%282%2F%28x%2B3%29%29=%28-4%29%2F%28x%5E2%2B10x%2B21%29\"\r
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\n" ); document.write( "\n" ); document.write( "To add the two terms on the left side, we need a Lowest Common Denominator, given by:\r
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\n" ); document.write( "\n" ); document.write( "\"%28x%2B7%29%28x%2B3%29=x%5E2%2B10x%2B21\"\r
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\n" ); document.write( "\n" ); document.write( "Now we have:\r
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\n" ); document.write( "\n" ); document.write( "Simplify:\r
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\n" ); document.write( "\n" ); document.write( "\"%283x%2B17%29%2F%28x%5E2%2B10x%2B21%29=%28-4%29%2F%28x%5E2%2B10x%2B21%29\"\r
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\n" ); document.write( "\n" ); document.write( "Since the denominators are equal on both sides, the numerators must be equal as well for the statement to be true, therefore:\r
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\n" ); document.write( "\n" ); document.write( "\"3x%2B17=-4\"
\n" ); document.write( "\"3x=-21\"
\n" ); document.write( "\"x=-21%2F3=-7\"\r
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\n" ); document.write( "\n" ); document.write( "But that causes a problem because -7 is not in the domain of either the y1 or y3 functions. x=-7 leads to a zero denominator in each case. Therefore, there are no values of x that satisfy the given conditions. Presuming my assumptions about the construct of the original problem were correct, that is.
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