document.write( "Question 114754: Can some one help me please.
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\n" ); document.write( "x^2 + 8x + 13 = 0\r
\n" ); document.write( "\n" ); document.write( "Thank you inadavance.
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Algebra.Com's Answer #83497 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "\"x%5E2%2B8x%2B13=0\" Start with the given equation\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2%2B8x=-13\" Subtract 13 from both sides\r
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\n" ); document.write( "\n" ); document.write( "Take half of the x coefficient 8 to get 4 (ie \"8%2F2=4\")\r
\n" ); document.write( "\n" ); document.write( "Now square 4 to get 16 (ie \"%284%29%5E2=16\")\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2%2B8x%2B16=-13%2B16\" Add this result (16) to both sides. Now the expression \"x%5E2%2B8x%2B16\" is a perfect square trinomial.\r
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\n" ); document.write( "\n" ); document.write( "\"%28x%2B4%29%5E2=-13%2B16\" Factor \"x%5E2%2B8x%2B16\" into \"%28x%2B4%29%5E2\" (note: if you need help with factoring, check out this solver)\r
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\n" ); document.write( "\n" ); document.write( "\"%28x%2B4%29%5E2=3\" Combine like terms on the right side\r
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\n" ); document.write( "\n" ); document.write( "\"x%2B4=0%2B-sqrt%283%29\" Take the square root of both sides\r
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\n" ); document.write( "\n" ); document.write( "\"x=-4%2B-sqrt%283%29\" Subtract 4 from both sides to isolate x.\r
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\n" ); document.write( "\n" ); document.write( "So the expression breaks down to\r
\n" ); document.write( "\n" ); document.write( "\"x=-4%2Bsqrt%283%29\" or \"x=-4-sqrt%283%29\"\r
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\n" ); document.write( "\n" ); document.write( "So our answer is approximately\r
\n" ); document.write( "\n" ); document.write( "\"x=-2.26794919243112\" or \"x=-5.73205080756888\"\r
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\n" ); document.write( "\n" ); document.write( "Here is visual proof\r
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\n" ); document.write( "\n" ); document.write( "\"+graph%28+500%2C+500%2C+-10%2C+10%2C+-10%2C+10%2C+x%5E2%2B8x%2B13%29+\" graph of \"y=x%5E2%2B8x%2B13\"\r
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\n" ); document.write( "\n" ); document.write( "When we use the root finder feature on a calculator, we would find that the x-intercepts are \"x=-2.26794919243112\" and \"x=-5.73205080756888\", so this verifies our answer.\r
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