Since the 40 degree angle and the bottom left angle both have the same red curve on them, the two angles are equal. So, they are both 40 degrees.
With this, we can make the equation
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To continue: know that the three angles of any triangle add up to 180 degrees. One of the angles in the left triangle is 90 degrees, as shown by the symbol that looks like a square. We can now make an equation where we add up all three angles in the left triangle, and set it equal to 180, like this:
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Now that we have 2 equations, we can find what x and y are. Let's first list the equations we got:
Now solve.
x is 3, y is 1.