Answer:
y = 27°
Explanation:
We know that in a triangle, all 3 angles add up to 180 degrees. So we can find the sum of the 2 angles we know to find out angle z, which is the angle across from y, and we know they have the same measure. 63 + 90(the measure of the angle across from x) = 153. We can then do 180 - 153 = 27, which is the measure of z. Since z is congruent to y, we know that y = 27 degrees.
Hope this helps :)