document.write( "Question 200198This question is from textbook Mathematics in Our World
\n" ); document.write( ": Can you please help me solve this equation.\r
\n" ); document.write( "\n" ); document.write( "\"x%5E2-2x-13=0\" \n" ); document.write( "
Algebra.Com's Answer #150499 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "\"x%5E2-2x-13=0\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "Notice that the quadratic \"x%5E2-2x-13\" is in the form of \"Ax%5E2%2BBx%2BC\" where \"A=1\", \"B=-2\", and \"C=-13\"\r
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\n" ); document.write( "\n" ); document.write( "Let's use the quadratic formula to solve for \"x\":\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-B+%2B-+sqrt%28+B%5E2-4AC+%29%29%2F%282A%29\" Start with the quadratic formula\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-%28-2%29+%2B-+sqrt%28+%28-2%29%5E2-4%281%29%28-13%29+%29%29%2F%282%281%29%29\" Plug in \"A=1\", \"B=-2\", and \"C=-13\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%282+%2B-+sqrt%28+%28-2%29%5E2-4%281%29%28-13%29+%29%29%2F%282%281%29%29\" Negate \"-2\" to get \"2\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%282+%2B-+sqrt%28+4-4%281%29%28-13%29+%29%29%2F%282%281%29%29\" Square \"-2\" to get \"4\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%282+%2B-+sqrt%28+4--52+%29%29%2F%282%281%29%29\" Multiply \"4%281%29%28-13%29\" to get \"-52\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%282+%2B-+sqrt%28+4%2B52+%29%29%2F%282%281%29%29\" Rewrite \"sqrt%284--52%29\" as \"sqrt%284%2B52%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%282+%2B-+sqrt%28+56+%29%29%2F%282%281%29%29\" Add \"4\" to \"52\" to get \"56\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%282+%2B-+sqrt%28+56+%29%29%2F%282%29\" Multiply \"2\" and \"1\" to get \"2\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%282+%2B-+2%2Asqrt%2814%29%29%2F%282%29\" Simplify the square root (note: If you need help with simplifying square roots, check out this solver) \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%282%29%2F%282%29+%2B-+%282%2Asqrt%2814%29%29%2F%282%29\" Break up the fraction. \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+1+%2B-+sqrt%2814%29\" Reduce. \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+1%2Bsqrt%2814%29\" or \"x+=+1-sqrt%2814%29\" Break up the expression. \r
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\n" ); document.write( "\n" ); document.write( "So the solutions are \"x+=+1%2Bsqrt%2814%29\" or \"x+=+1-sqrt%2814%29\" \r
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\n" ); document.write( "\n" ); document.write( "which approximate to \"x=4.742\" or \"x=-2.742\"
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