document.write( "Question 243094: I need help setting up this problem. \r
\n" ); document.write( "\n" ); document.write( "The sum of a certain number and a second number is 21.
\n" ); document.write( "The second number minus the first number is -57.
\n" ); document.write( "Use a system of two equations with two variables to find the numbers.
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Algebra.Com's Answer #178105 by stanbon(75887)\"\" \"About 
You can put this solution on YOUR website!
I need help setting up this problem.
\n" ); document.write( "The sum of a certain number and a second number is 21.
\n" ); document.write( "The second number minus the first number is -57.
\n" ); document.write( "---------------------------
\n" ); document.write( "Equations:
\n" ); document.write( "x + y = 21
\n" ); document.write( "x - y = -57
\n" ); document.write( "--------------------------
\n" ); document.write( "Add the two equations and solve for \"x\":
\n" ); document.write( "2x = -36
\n" ); document.write( "x = -18
\n" ); document.write( "----------------------------------
\n" ); document.write( "Since x + y = 21
\n" ); document.write( "-18 + y = 21
\n" ); document.write( "y = 39
\n" ); document.write( "===============
\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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