document.write( "Question 778082: The square root of a number is subtracted from the sum of the number and 12. The result is 42. What is the original number? \n" ); document.write( "
Algebra.Com's Answer #474487 by ankor@dixie-net.com(22740)\"\" \"About 
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The square root of a number is subtracted from the sum of the number and 12.
\n" ); document.write( " The result is 42. What is the original number?
\n" ); document.write( ":
\n" ); document.write( "Just write an equation for what it says:
\n" ); document.write( "n + 12 - \"sqrt%28n%29\" = 42
\n" ); document.write( "subtract 12 from both sides
\n" ); document.write( "n - \"sqrt%28n%29\" = 30
\n" ); document.write( "we can also write it:
\n" ); document.write( "n - 30 = \"sqrt%28n%29\"
\n" ); document.write( "Square both sides
\n" ); document.write( "n^2 - 60n + 900 = n
\n" ); document.write( "Arrange as a quadratic equation
\n" ); document.write( "n^2 - 60n - n + 900 = 0
\n" ); document.write( "n^2 - 61n + 900 = 0
\n" ); document.write( "Factors to
\n" ); document.write( "(n-25)(n-36) = 0
\n" ); document.write( "Two solutions
\n" ); document.write( "n = 25
\n" ); document.write( "and
\n" ); document.write( "n = 36
\n" ); document.write( ":
\n" ); document.write( "See if n=36 works
\n" ); document.write( "36 + 12 - \"sqrt%2836%29\" = 42
\n" ); document.write( "48 - 6 = 42, OK
\n" ); document.write( ":
\n" ); document.write( "do the same with n=25
\n" ); document.write( "25 + 12 - \"sqrt%2825%29\" = 42
\n" ); document.write( "37 - 5 does not equal 42, so n=25 if not a solution \n" ); document.write( "
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