Answer:
120 degrees
Explanation:
These are called supplementary angles. These are angles that add up to 180 degrees.
To solve this, you need to know that a triangle's interior angles should all add up to 180 degrees, no matter how weird the triangle looks.
For squares and other stuff it's 360 degrees
But as shown, all three interior angles of this triangle are the same. This means each of them is 60 degrees.
60 + 60 + 60 = 180
-----------------------------------------------------------------------------------------------------------------
To find X, we know that the angle of a straight line is 180 degrees. Since X and that one interior angle share the same line,
we subtract 60 from 180 to get the remaining angle of X.
180 - 60 = 120 degrees.