CEMC Fermat

Algebra Difficulty 1.9 Junior Find the answer

If $3+x=5$ and $-3+y=5$ , what is the value of $x+y$ ?

Your answer

A number or a short expression. Fractions can be typed as 3/2, and spacing doesn't matter.

Solution

Since $3+x=5$ , then $x=2$ . Since $-3+y=5$ , then $y=8$ . Thus, $x+y=10$ . Alternatively, we could have added the original two equations to obtain $(3+x)+(-3+y)=5+5$ which simplifies to $x+y=10$ .

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