document.write( "Question 115480: Factoring to solve Quadratic Equations.
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\n" ); document.write( "\n" ); document.write( "1. x squared + 7x = 8\r
\n" ); document.write( "\n" ); document.write( "2. x squared = 25\r
\n" ); document.write( "\n" ); document.write( "3. 2t squared + 8t - 64 =0\r
\n" ); document.write( "\n" ); document.write( "4. 3a squared - 36a + 81 = 0\r
\n" ); document.write( "\n" ); document.write( "5. 2a squared - a - 21 = 0
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Algebra.Com's Answer #84042 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
I'll do the first few to give you an idea how to do these\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2%2B7x=8\" Start with the given equation\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2%2B7x-8=0\" Move all of the terms to the left side\r
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\n" ); document.write( "\n" ); document.write( "\"%28x%2B8%29%28x-1%29=0\" Factor the left side (note: if you need help with factoring, check out this solver)\r
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\n" ); document.write( "\n" ); document.write( "Now set each factor equal to zero:\r
\n" ); document.write( "\n" ); document.write( "\"x%2B8=0\" or \"x-1=0\" \r
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\n" ); document.write( "\n" ); document.write( "\"x=-8\" or \"x=1\" Now solve for x in each case\r
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\n" ); document.write( "\n" ); document.write( "So our answer is \r
\n" ); document.write( "\n" ); document.write( " \"x=-8\" or \"x=1\" \r
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\n" ); document.write( "\n" ); document.write( "Notice if we graph \"y=x%5E2%2B7x-8\" we can see that the roots are \"x=-8\" and \"x=1\" . So this visually verifies our answer.\r
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\n" ); document.write( "\n" ); document.write( "\"+graph%28500%2C500%2C-10%2C10%2C-10%2C10%2C0%2C+x%5E2%2B7x-8%29+\"\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2=25\" Start with the given equation\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2-25=0\" Move all of the terms to the left side\r
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\n" ); document.write( "\n" ); document.write( "\"%28x%2B5%29%28x-5%29=0\" Factor the left side (note: if you need help with factoring, check out this solver)\r
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\n" ); document.write( "\n" ); document.write( "Now set each factor equal to zero:\r
\n" ); document.write( "\n" ); document.write( "\"x%2B5=0\" or \"x-5=0\" \r
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\n" ); document.write( "\n" ); document.write( "\"x=-5\" or \"x=5\" Now solve for x in each case\r
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\n" ); document.write( "\n" ); document.write( "So our answer is \r
\n" ); document.write( "\n" ); document.write( " \"x=-5\" or \"x=5\" \r
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\n" ); document.write( "\n" ); document.write( "Notice if we graph \"y=x%5E2-25\" we can see that the roots are \"x=-5\" and \"x=5\" . So this visually verifies our answer.\r
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\n" ); document.write( "\n" ); document.write( "\"+graph%28500%2C500%2C-10%2C10%2C-10%2C10%2C0%2C+x%5E2-25%29+\"\r
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\n" ); document.write( "\n" ); document.write( "\"2t%5E2%2B8t-64=0\" Start with the given equation\r
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\n" ); document.write( "\n" ); document.write( "\"2%28t%5E2%2B4t-32%29=0\" Factor out the GCF 2\r
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\n" ); document.write( "\n" ); document.write( "\"2%28t%2B8%29%28t-4%29=0\" Factor the inner expression (note: if you need help with factoring, check out this solver)\r
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\n" ); document.write( "\n" ); document.write( "Now set each factor equal to zero:\r
\n" ); document.write( "\n" ); document.write( "\"t%2B8=0\" or \"t-4=0\" \r
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\n" ); document.write( "\n" ); document.write( "\"t=-8\" or \"t=4\" Now solve for t in each case\r
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\n" ); document.write( "\n" ); document.write( "So our answer is \r
\n" ); document.write( "\n" ); document.write( " \"t=-8\" or \"t=4\" \r
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\n" ); document.write( "\n" ); document.write( "Notice if we graph \"y=2t%5E2%2B8t-64\" we can see that the roots are \"t=-8\" and \"t=4\" . So this visually verifies our answer.\r
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\n" ); document.write( "\n" ); document.write( "\"+graph%28500%2C500%2C-10%2C10%2C-10%2C10%2C0%2C+2x%5E2%2B8x-64%29+\"
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