document.write( "Question 878712: A number is such that it is as much greater than 84 as it is less than 108. find it
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Algebra.Com's Answer #530226 by KMST(5328)\"\" \"About 
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MENTAL MATH:
\n" ); document.write( "I would average the two numbers in my head, and come up with \"highlight%2896%29\" .
\n" ); document.write( "In my head I really average their differences to 100.
\n" ); document.write( "I see 84 as 84 - 100 = -16, and I see 108 as 8.
\n" ); document.write( "I add -16+8=-8, and divide by 2 to find the average as -4.
\n" ); document.write( "That means that the number is -4 + 100 = 96.
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\n" ); document.write( "SYSTEM OF EQUATIONS:
\n" ); document.write( "\"x\"= the number
\n" ); document.write( "\"y\"= how much greater than 84 the number is
\n" ); document.write( "Since the number is that much greater than 84 the number is
\n" ); document.write( "\"x=84%2By\" .
\n" ); document.write( "Since the number is that much less than 108 the number is
\n" ); document.write( "\"x=108-y\" .
\n" ); document.write( "So we write the system of equations
\n" ); document.write( "\"system%28x=84%2By%2Cx=108-y%29\"
\n" ); document.write( "and we solve it by institution, substituting the expression \"108-y\" for \"x%7D%7D+in+%7B%7B%7Bx=84%2By\" , to get
\n" ); document.write( "\"108-y=84%2By\" .
\n" ); document.write( "We solve for \"y\" , and then we plug the value found for \"y\" into either of the original equations yo find \"x\" .
\n" ); document.write( "\"108-y=84%2By\"-->\"108=84%2By%2By\"-->\"108=84%2B2y\"-->\"108-84=2y\"-->\"24=2y\"-->\"24%2F2=y\"-->\"highlight%28y=12%29\"
\n" ); document.write( "\"system%28x=84%2By%2Cy=12%29\" ---> \"x=84%2B12\" ---> \"highlight%28x=96%29\"
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\n" ); document.write( "There are many other ways to solve it.
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