document.write( "Question 1006489: y-4/y^2-y-20\r
\n" ); document.write( "\n" ); document.write( "A) 0 and -5 B)0 and 5 C) 4 and -5 D) -4 and 5 \n" ); document.write( "
Algebra.Com's Answer #622619 by ikleyn(52781)\"\" \"About 
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\n" ); document.write( "Comment from student: Find the value of x that must be excluded in the algebraic fraction: y-4/y^2-y-20 — Thanks
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\n" ); document.write( "\n" ); document.write( "Let us consider the denominator of this function which is a quadratic polynomial p(x) = \"y%5E2-y-20\".\r
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\n" ); document.write( "\n" ); document.write( "It can be factored as p(y) = (y-5)*(y+4).\r
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\n" ); document.write( "\n" ); document.write( "It has the roots y = 5 and y = -4.\r
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\n" ); document.write( "\n" ); document.write( "Hence, the domain of the given rational function is the entire number line except two points y = 5 and y = -4, where the function is not defined.\r
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