document.write( "Question 115166: how do you solve by completing the square if your problem is: xsq-14x+1=0 ? \n" ); document.write( "
Algebra.Com's Answer #83874 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!

\n" ); document.write( "\"x%5E2-14x%2B1=0\" Start with the given equation\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2-14x=-1\" Subtract 1 from both sides\r
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\n" ); document.write( "\n" ); document.write( "Take half of the x coefficient -14 to get -7 (ie \"-14%2F2=-7\")\r
\n" ); document.write( "\n" ); document.write( "Now square -7 to get 49 (ie \"%28-7%29%5E2=49\")\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2-14x%2B49=-1%2B49\" Add this result (49) to both sides. Now the expression \"x%5E2-14x%2B49\" is a perfect square trinomial.\r
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\n" ); document.write( "\n" ); document.write( "\"%28x-7%29%5E2=-1%2B49\" Factor \"x%5E2-14x%2B49\" into \"%28x-7%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-7%29%5E2=48\" Combine like terms on the right side\r
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\n" ); document.write( "\n" ); document.write( "\"x-7=0%2B-sqrt%2848%29\" Take the square root of both sides\r
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\n" ); document.write( "\n" ); document.write( "\"x=7%2B-sqrt%2848%29\" Add 7 to 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=7%2Bsqrt%2848%29\" or \"x=7-sqrt%2848%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=13.9282032302755\" or \"x=0.0717967697244912\"\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+15%2C+-10%2C+10%2C+x%5E2-14x%2B1%29+\" graph of \"y=x%5E2-14x%2B1\"\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=13.9282032302755\" and \"x=0.0717967697244912\", so this verifies our answer.\r
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