document.write( "Question 59405: x^2-9<0
\n" ); document.write( "solve the inequality. \n" ); document.write( "

Algebra.Com's Answer #40703 by funmath(2933) $\"\"$ $\"About$

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$\"x%5E2-9%3C0\"$
\n" ); document.write( "solve the inequality.
\n" ); document.write( "Find the numbers that make the equation equal 0.
\n" ); document.write( " $\"%28x%2B3%29%28x-3%29=0\"$
\n" ); document.write( "x+3=0 and x-3=0
\n" ); document.write( "x+3-3=0-3 and x-3+3=0+3
\n" ); document.write( "x=-3 and x=3
\n" ); document.write( "Now you test the intervals (-infinity,-3), (-3,3), (3,infinity)
\n" ); document.write( "By plugging in a test number of your choice in each number, if the result is less than 0 (negative) the interval is part of the solution.
\n" ); document.write( "For (-infinity,-3) test -4
\n" ); document.write( " $\"%28-4%29%5E2-9\"$
\n" ); document.write( " $\"16-9\"$
\n" ); document.write( " $\"7\"$ 7 is greater tahn 0 (positive), so the interval is not included.
\n" ); document.write( "For (-3,3) test 0
\n" ); document.write( " $\"%280%29%5E2-9\"$
\n" ); document.write( " $\"0-9\"$
\n" ); document.write( " $\"-9\"$ -9 is less than 0 (negative), so (-3,3) is part of the solution.
\n" ); document.write( "For (3,infinity) test 4
\n" ); document.write( " $\"%284%29%5E2-9\"$
\n" ); document.write( " $\"16-9\"$
\n" ); document.write( " $\"7\"$ is greater than 0 (positive), so (3,infinity) is not part of the solution.
\n" ); document.write( "The soltuion is (-3,3) in interval notation
\n" ); document.write( " $\"-3%3Cx%3C3\"$ is also a notation commonly used.
\n" ); document.write( ":
\n" ); document.write( "Notice that if the inequality was $\"x%5E2-9%3E0\"$ , the soltuion would have been (-infinity,-3)U(3,infinity). Think about it and fun with it.
\n" ); document.write( "Happy Calculating!!! \n" ); document.write( "

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