document.write( "Question 180712: My book gives an example of an quadratic equation, but I do not understand how it has been worked. Here is the one that I have to turn in on my home work x2-2x-13=0,and here is the example from the book: My e-mail address is, glen.a.harris@windstream.net\r
\n" ); document.write( "\n" ); document.write( "x2+3x-10=0
\n" ); document.write( "x2+3x=10
\n" ); document.write( "4x2+12x=40
\n" ); document.write( "4x2+12x+9=40+9
\n" ); document.write( "4x2+12x+9=49
\n" ); document.write( "2x+3=+7\r
\n" ); document.write( "\n" ); document.write( "2x+3=7 2x+3=-7
\n" ); document.write( "2x=4 2x=-10
\n" ); document.write( "x=2 x=-5
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Algebra.Com's Answer #135434 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
I'm not sure of the method that you're using, but here's the way that I'd do it:\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2%2B3x-10=0\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "Notice we have a quadratic equation in the form of \"ax%5E2%2Bbx%2Bc\" where \"a=1\", \"b=3\", and \"c=-10\"\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-%283%29+%2B-+sqrt%28+%283%29%5E2-4%281%29%28-10%29+%29%29%2F%282%281%29%29\" Plug in \"a=1\", \"b=3\", and \"c=-10\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-3+%2B-+sqrt%28+9-4%281%29%28-10%29+%29%29%2F%282%281%29%29\" Square \"3\" to get \"9\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-3+%2B-+sqrt%28+9--40+%29%29%2F%282%281%29%29\" Multiply \"4%281%29%28-10%29\" to get \"-40\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-3+%2B-+sqrt%28+9%2B40+%29%29%2F%282%281%29%29\" Rewrite \"sqrt%289--40%29\" as \"sqrt%289%2B40%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-3+%2B-+sqrt%28+49+%29%29%2F%282%281%29%29\" Add \"9\" to \"40\" to get \"49\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-3+%2B-+sqrt%28+49+%29%29%2F%282%29\" Multiply \"2\" and \"1\" to get \"2\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-3+%2B-+7%29%2F%282%29\" Take the square root of \"49\" to get \"7\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-3+%2B+7%29%2F%282%29\" or \"x+=+%28-3+-+7%29%2F%282%29\" Break up the expression. \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%284%29%2F%282%29\" or \"x+=++%28-10%29%2F%282%29\" Combine like terms. \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+2\" or \"x+=+-5\" Simplify. \r
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\n" ); document.write( "\n" ); document.write( "So the answers are \"x+=+2\" or \"x+=+-5\" \r
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