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Triangular Algebra

Age 14 to 16 Short
Challenge Level


The interior angles of a triangle are $\left(5x+3y\right)^\circ$, $\left(10y+30\right)^\circ$ and $\left(3x+20\right)^\circ$, where $x$ and $y$ are positive integers.

What is the value of $x+y$?





If you liked this problem, here is an NRICH task that challenges you to use similar mathematical ideas.

This problem is taken from the UKMT Mathematical Challenges.
You can find more short problems, arranged by curriculum topic, in our short problems collection.