Answer:
Y is 90 degrees.
Explanation:
This is an equalterial triangle which means all of the angles are the same. The angle for the upper part of the triangle is 60 as well. We can do 2x=60 because they add up to the angle which is 60. This gives us x=30. If x=30 and the other angle is 60, then the other angle has to be 90 because all triangle has an angle sum of 180. So 30 +60 + 90= 180. Hope this helps!