Answer:
120 degrees
Explanation:
Because the triangle is a right triangle, it can be either a 45,45,90 triangle or a 30,60,90 triangle. I tested this problem with each scenerio, and I believe that it is a 30, 60, 90 triangle, with the top angle being 30 degrees, thus, making x=30. For the exterior angle, we'd multiply 4 by 30 to get 120 degrees.
I checked my answer by adding 120 to 60 (that's the degrees of the right hand corner of the triangle), which added to 180 degrees (aka a flat line), which verifies my answer.
I hope this helps! :)