document.write( "Question 185547: The sum of a positive number and its square is 12. What is the number? \n" ); document.write( "
Algebra.Com's Answer #139198 by jim_thompson5910(35256)\"\" \"About 
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\"The sum of a positive number and its square is 12\" translates to \"x%2Bx%5E2=12\"\r
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\n" ); document.write( "\n" ); document.write( "\"x%2Bx%5E2=12\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"x%2Bx%5E2-12=0\" Subtract 12 from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2%2Bx-12=0\" Rearrange the terms.\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=1\", and \"c=-12\"\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-%281%29+%2B-+sqrt%28+%281%29%5E2-4%281%29%28-12%29+%29%29%2F%282%281%29%29\" Plug in \"a=1\", \"b=1\", and \"c=-12\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-1+%2B-+sqrt%28+1-4%281%29%28-12%29+%29%29%2F%282%281%29%29\" Square \"1\" to get \"1\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-1+%2B-+sqrt%28+1--48+%29%29%2F%282%281%29%29\" Multiply \"4%281%29%28-12%29\" to get \"-48\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-1+%2B-+sqrt%28+1%2B48+%29%29%2F%282%281%29%29\" Rewrite \"sqrt%281--48%29\" as \"sqrt%281%2B48%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-1+%2B-+sqrt%28+49+%29%29%2F%282%281%29%29\" Add \"1\" to \"48\" to get \"49\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-1+%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+=+%28-1+%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+=+%28-1+%2B+7%29%2F%282%29\" or \"x+=+%28-1+-+7%29%2F%282%29\" Break up the expression. \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%286%29%2F%282%29\" or \"x+=++%28-8%29%2F%282%29\" Combine like terms. \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+3\" or \"x+=+-4\" Simplify. \r
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\n" ); document.write( "\n" ); document.write( "So the possible answers are \"x+=+3\" or \"x+=+-4\" \r
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\n" ); document.write( "\n" ); document.write( "However, the problem states that the number is positive. So we must ignore \"x=-4\"\r
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\n" ); document.write( "\n" ); document.write( "So the only answer is \"x=3\" which means that the number is 3\r
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