document.write( "Question 161996: if a number is added to its square,the result is 42.find the number. \n" ); document.write( "
Algebra.Com's Answer #119379 by MathLover1(20849)\"\" \"About 
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\n" ); document.write( "let number be \"x\"....
\n" ); document.write( "if a number (\"x\") is added to its square (\"x%5E2\"),the result is \"42\"\r
\n" ); document.write( "\n" ); document.write( "\"x+%2B+x%5E2+=+42\" or\r
\n" ); document.write( "\n" ); document.write( "\"x%5E2+%2B+x+-42+=+0\".....use quadratic formula\r
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Solved by pluggable solver: Quadratic Formula
Let's use the quadratic formula to solve for x:

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\n" ); document.write( " Starting with the general quadratic
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\n" ); document.write( " \"ax%5E2%2Bbx%2Bc=0\"
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\n" ); document.write( " the general solution using the quadratic equation is:
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\n" ); document.write( " \"x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29\"
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\n" ); document.write( " So lets solve \"x%5E2%2Bx-42=0\" ( notice \"a=1\", \"b=1\", and \"c=-42\")
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\n" ); document.write( " \"x+=+%28-1+%2B-+sqrt%28+%281%29%5E2-4%2A1%2A-42+%29%29%2F%282%2A1%29\" Plug in a=1, b=1, and c=-42
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\n" ); document.write( " \"x+=+%28-1+%2B-+sqrt%28+1-4%2A1%2A-42+%29%29%2F%282%2A1%29\" Square 1 to get 1
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\n" ); document.write( " \"x+=+%28-1+%2B-+sqrt%28+1%2B168+%29%29%2F%282%2A1%29\" Multiply \"-4%2A-42%2A1\" to get \"168\"
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\n" ); document.write( " \"x+=+%28-1+%2B-+sqrt%28+169+%29%29%2F%282%2A1%29\" Combine like terms in the radicand (everything under the square root)
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\n" ); document.write( " \"x+=+%28-1+%2B-+13%29%2F%282%2A1%29\" Simplify the square root (note: If you need help with simplifying the square root, check out this solver)
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\n" ); document.write( " \"x+=+%28-1+%2B-+13%29%2F2\" Multiply 2 and 1 to get 2
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\n" ); document.write( " So now the expression breaks down into two parts
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\n" ); document.write( " \"x+=+%28-1+%2B+13%29%2F2\" or \"x+=+%28-1+-+13%29%2F2\"
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\n" ); document.write( " Lets look at the first part:
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\n" ); document.write( " \"x=%28-1+%2B+13%29%2F2\"
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\n" ); document.write( " \"x=12%2F2\" Add the terms in the numerator
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\n" ); document.write( " \"x=6\" Divide
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\n" ); document.write( " So one answer is
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\n" ); document.write( " \"x=6\"
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\n" ); document.write( " Now lets look at the second part:
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\n" ); document.write( " \"x=%28-1+-+13%29%2F2\"
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\n" ); document.write( " \"x=-14%2F2\" Subtract the terms in the numerator
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\n" ); document.write( " \"x=-7\" Divide
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\n" ); document.write( " So another answer is
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\n" ); document.write( " \"x=-7\"
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\n" ); document.write( " So our solutions are:
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\n" ); document.write( " \"x=6\" or \"x=-7\"
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\n" ); document.write( "\n" ); document.write( "so, one answer is \"x=6\" and another answer is \"x=-7\"\r
\n" ); document.write( "\n" ); document.write( "check:\r
\n" ); document.write( "\n" ); document.write( "\"x+%2B+x%5E2+=+42\"\r
\n" ); document.write( "\n" ); document.write( "\"6+%2B+6%5E2+=+42\"\r
\n" ); document.write( "\n" ); document.write( "\"6+%2B+36+=+42\"\r
\n" ); document.write( "\n" ); document.write( "\"42+=+42\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+%2B+x%5E2+=+42\"\r
\n" ); document.write( "\n" ); document.write( "\"-7+%2B+%28-7%29%5E2+=+42\"\r
\n" ); document.write( "\n" ); document.write( "\"-7+%2B+49=+42\"\r
\n" ); document.write( "\n" ); document.write( "\"42+=+42\"\r
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