Numbers question?

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1 Answer
May 17, 2018

#4.5# and #9.5#

Explanation:

Me

You start by writing two equations, #x+y=13# and #x-y=4#. We know these as the two numbers added become #13# and when subtracted become #4#.

I worked with the second equation, adding the #y# to both sides to get #x=y+4#. I moved this new equation to the first equation, substituting the #y+4# for #x#.

I then had #(y+4) + y =13#.

Keeping the variables on one side and the numbers on the other, it results in #2y=9#. I divide by two on both sides.

This results in #y=4.5#. We then bring this new result back into the original second equation.

So now we have #x-4.5 = 4#. Add #4.5# to both sides, and we get #x = 9.5#.