



 
Hi Elisabeth, You can certainly solve the problem with the two variables $x$ and $y.$ You then have two equations. Since the sum is 8 you know that $x + y = 8.$ The difference is 4 so write this as an equation also and solve the resulting two equations for $x$ and $y.$ I would however prefer to approach the problem this way. Let $x$ be the greater of the two numbers. Since their difference is 4 you know the second number is 4 less than $x$ so it is $x  4.$ The sum of the two numbers is 8 so $x + x  4 = 8.$ solve for $x.$ Penny  


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