document.write( "Question 447707: There are two numbers whose sum is 9 and the difference is five . What are the two numbers? \n" ); document.write( "
Algebra.Com's Answer #308169 by Leaf W.(135)\"\" \"About 
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You can do this two ways: with one variable or with two variables. Personally, I think one variable is easier, but I'll show you both.
\n" ); document.write( "1. ONE variable
\n" ); document.write( "\"two numbers WHOSE SUM IS 9\"
\n" ); document.write( "x = one number
\n" ); document.write( "9 - x = other number (since the sum of the two numbers is 9, and one of them is x, then the other number would be the remainder or the difference when x is subtracted from 9
\n" ); document.write( "\"the difference is five\"
\n" ); document.write( "(9 - x) - x = 5
\n" ); document.write( "9 - x - x = 5
\n" ); document.write( "9 - 2x = 5
\n" ); document.write( "Subtract 9 from both sides: -2x = -4
\n" ); document.write( "Divide both sides by -2: x = 2
\n" ); document.write( "One of the numbers is 2. Plug this into the expression for the other number to find the other number.
\n" ); document.write( "9 - x
\n" ); document.write( "9 - 2
\n" ); document.write( "7
\n" ); document.write( "***THEREFORE, THE NUMBERS ARE 2 AND 7.
\n" ); document.write( "2. TWO variables
\n" ); document.write( "x = one number
\n" ); document.write( "y = other number
\n" ); document.write( "\"whose sum is 9\"
\n" ); document.write( "x + y = 9
\n" ); document.write( "\"and the difference is five\"
\n" ); document.write( "x - y = 5
\n" ); document.write( "Solve as a system of equations by \"adding\" the two equations.
\n" ); document.write( "x + y = 9
\n" ); document.write( "+(x - y = 5)
\n" ); document.write( "-----------
\n" ); document.write( "2x + 0y = 14
\n" ); document.write( "2x = 14
\n" ); document.write( "x = 7
\n" ); document.write( "Plug this value for x into either of the two equations and solve for y to find the value of the other number.
\n" ); document.write( "x + y = 9
\n" ); document.write( "7 + y = 9
\n" ); document.write( "y = 2
\n" ); document.write( "***THEREFORE, THE NUMBERS ARE TWO AND SEVEN.
\n" ); document.write( "
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