document.write( "Question 201219: Can someone please help me solve the inequality.\r
\n" ); document.write( "\n" ); document.write( "p^3 - 16p (less than or equal to) 0
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Algebra.Com's Answer #151421 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!

\n" ); document.write( "\"p%5E3-16p%3C=0\" Start with the given inequality\r
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\n" ); document.write( "\n" ); document.write( "\"p%28p-4%29%28p%2B4%29%3C=0\" Factor the left side\r
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\n" ); document.write( "\n" ); document.write( "\"p%28p-4%29%28p%2B4%29=0\" Set the left side equal to zero\r
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\n" ); document.write( "\n" ); document.write( "Set each individual factor equal to zero:\r
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\n" ); document.write( "\n" ); document.write( "\"p=0\", \"p-4=0\" or \"p%2B4=0\" \r
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\n" ); document.write( "\n" ); document.write( "Solve for p in each case:\r
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\n" ); document.write( "\n" ); document.write( "\"p=0\", \"p=4\" or \"p=-4\" \r
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\n" ); document.write( "\n" ); document.write( "So our critical values are \"p=0\", \"p=4\" and \"p=-4\" \r
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\n" ); document.write( "\n" ); document.write( "Now set up a number line and plot the critical values on the number line\r
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\n" ); document.write( "\n" ); document.write( "\"number_line%28+600%2C+-10%2C+10%2C0%2C4%2C-4%29\"\r
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\n" ); document.write( "\n" ); document.write( "So let's pick some test points that are near the critical values and evaluate them.\r
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\n" ); document.write( "\n" ); document.write( "Let's pick a test value that is less than \"-4\" (notice how it's to the left of the leftmost endpoint). This will determine if the interval (] is part of the solution set.\r
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\n" ); document.write( "\n" ); document.write( "So let's pick \"p=-5\"\r
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\n" ); document.write( "\n" ); document.write( "\"p%28p-4%29%28p%2B4%29%3C=0\" Start with the given inequality\r
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\n" ); document.write( "\n" ); document.write( "\"-5%28-5-4%29%28-5%2B4%29%3C=+0\" Plug in \"p=-5\"\r
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\n" ); document.write( "\n" ); document.write( "\"-45%3C=+0\" Evaluate and simplify the left side\r
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\n" ); document.write( "\n" ); document.write( "Since the inequality is true, this means that the interval works. So this tells us that this interval is in our solution set.\r
\n" ); document.write( "\n" ); document.write( " So part our solution in interval notation is (]\r
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\n" ); document.write( "\n" ); document.write( "Let's pick a test value that is in between \"-4\" and \"0\". This will determine if the interval [] is part of the solution set.\r
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\n" ); document.write( "\n" ); document.write( "So let's pick \"p=-2\"\r
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\n" ); document.write( "\n" ); document.write( "\"p%28p-4%29%28p%2B4%29%3C=0\" Start with the given inequality\r
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\n" ); document.write( "\n" ); document.write( "\"-2%28-2-4%29%28-2%2B4%29%3C=+0\" Plug in \"p=0\"\r
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\n" ); document.write( "\n" ); document.write( "\"24%3C=+0\" Evaluate and simplify the left side\r
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\n" ); document.write( "\n" ); document.write( "Since the inequality is false, this means that we can ignore this interval.\r
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\n" ); document.write( "\n" ); document.write( "Now let's pick a test value that is in between \"0\" and \"4\" to see if the interval [] is in the solution set \r
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\n" ); document.write( "\n" ); document.write( "So let's pick \"p=2\"\r
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\n" ); document.write( "\n" ); document.write( "\"p%28p-4%29%28p%2B4%29%3C=0\" Start with the given inequality\r
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\n" ); document.write( "\n" ); document.write( "\"2%282-4%29%282%2B4%29%3C=+0\" Plug in \"p=5\"\r
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\n" ); document.write( "\n" ); document.write( "\"-24%3C=+0\" Evaluate and simplify the left side\r
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\n" ); document.write( "\n" ); document.write( "Since the inequality is true, this means that the interval [] is in the solution set.\r
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\n" ); document.write( "\n" ); document.write( "Now let's pick a test value that is greater than \"4\" to see if the interval [) is in the solution set \r
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\n" ); document.write( "\n" ); document.write( "So let's pick \"p=5\"\r
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\n" ); document.write( "\n" ); document.write( "\"p%28p-4%29%28p%2B4%29%3C=0\" Start with the given inequality\r
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\n" ); document.write( "\n" ); document.write( "\"5%285-4%29%285%2B4%29%3C=+0\" Plug in \"p=5\"\r
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\n" ); document.write( "\n" ); document.write( "\"45%3C=+0\" Evaluate and simplify the left side\r
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\n" ); document.write( "\n" ); document.write( "Since the inequality is false, this means that we can ignore this interval.\r
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\n" ); document.write( "\n" ); document.write( "Summary:\r
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\n" ); document.write( "\n" ); document.write( "So the solution in interval notation is:\r
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\n" ); document.write( "\n" ); document.write( "(] []\r
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