document.write( "Question 1196593: 4x^2+5x-9 over x^2-x - 6 ≥ 0
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Algebra.Com's Answer #829494 by greenestamps(13200)\"\" \"About 
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\n" ); document.write( "*** Revised to correct silly arithmetic error....***

\n" ); document.write( "To find where the inequality is satisfied, we need to determine the values of x where the sign of the function changes; that can happen only at values of x for which the numerator and/or denominator is 0.

\n" ); document.write( "So factor the numerator and denominator to identify those values of x.

\n" ); document.write( "\"%284x%5E2%2B5x-9%29%2F%28x%5E2-x-6%29%3E=0\"

\n" ); document.write( "\"%28%284x%2B9%29%28x-1%29%29%2F%28%28x-3%29%28x%2B2%29%29%3E=0\"

\n" ); document.write( "The function value is 0 and changes sign when the numerator is 0 -- at x = -9/4 and x = 1.

\n" ); document.write( "The function is undefined and its value changes sign when the denominator is 0 -- at x = -2 and x = 3.

\n" ); document.write( "For \"large\" values of x (greater than 3), all the factors in the factored form of the function are positive, so the function value is positive.

\n" ); document.write( "And the function value changes sign at x = -9/4, -2, 1, and 3. That means the function value is...

\n" ); document.write( "positive for x greater than 3;
\n" ); document.write( "negative for x between 1 and 3;
\n" ); document.write( "positive for x between -2 and 1;
\n" ); document.write( "negative for x between -9/4 and -2; and
\n" ); document.write( "positive for x less than -9/4

\n" ); document.write( "Finally, remembering that the function is 0 at -9/4 and 1 and undefined at -2 and 3, the solution set to the inequality is

\n" ); document.write( "(-infinity,-9/4] U (-2,1] U (3,infinity)

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