document.write( "Question 1025457: A) Find the y intercepts B) Find the x intercepts and C) find the intervals of x where f(x) > 0 and those where f(x) <0. Do not sketch the graph.\r
\n" ); document.write( "\n" ); document.write( "f(x) = (x-5) (x+4) (x-3) \n" ); document.write( "
Algebra.Com's Answer #640729 by Fombitz(32388)\"\" \"About 
You can put this solution on YOUR website!
A) When \"x=0\",
\n" ); document.write( "\"f%280%29=%28-5%29%284%29%28-3%29=60\"
\n" ); document.write( "B) \"x-5=0\"
\n" ); document.write( "\"x=5\"
\n" ); document.write( "and
\n" ); document.write( "\"x%2B4=0\"
\n" ); document.write( "\"x=-4\"
\n" ); document.write( "and
\n" ); document.write( "\"x-3=0\"
\n" ); document.write( "\"x=3\"
\n" ); document.write( "C) Break up the number line into regions using the x-intercepts,
\n" ); document.write( "Region 1 : ( \"-infinity\",\"-4\")
\n" ); document.write( "Region 2 : (\"-4\",\"3\")
\n" ); document.write( "Region 3 : (\"3\",\"5\")
\n" ); document.write( "Region 4 : (\"5\",\"infinity\")
\n" ); document.write( "Pick a point in each region and test the function to see if its greater than or less than zero.
\n" ); document.write( "Region 1 : \"x=-5\"
\n" ); document.write( "\"f%28-5%29=%28-5-5%29%28-5%2B4%29%28-5-3%29=%28-10%29%28-1%29%28-8%29=-80\"
\n" ); document.write( "Region 2 : \"x=0\"
\n" ); document.write( "\"f%280%29=60\"
\n" ); document.write( "Region 3 : \"x=4\"
\n" ); document.write( "\"f%284%29=%284-5%29%284%2B4%29%284-3%29=%28-1%29%288%29%281%29=-8\"
\n" ); document.write( "Region 4 : \"x=6\"
\n" ); document.write( "\"f%286%29=%286-5%29%286%2B4%29%286-3%29=%281%29%2810%29%283%29=30\"
\n" ); document.write( "So then,
\n" ); document.write( " ( \"-infinity%3Cx%3C-4\") , \"f%28x%29%3C0\"
\n" ); document.write( "(\"-4%3Cx%3C3\") \"f%28x%29%3E0\"\r
\n" ); document.write( "\n" ); document.write( " (\"3%3Cx%3C5\"), \"f%28x%29%3C0\"\r
\n" ); document.write( "\n" ); document.write( "(\"5%3Cx%3Cinfinity\"), \"f%28x%29%3E0\"
\n" ); document.write( " \n" ); document.write( "
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