This is simple :p The answers are all already there for you. Here, think about it as two triangles instead of a parallelogram. The triangles are BOTH EXACTLY identical, so what one triangle has, the other will have! We all know triangles should ALWAYS equal up to 180 degrees. Angle Z is identical to another point. The unmarked angle with no letter is identical to another point, right next to it. Use that into, and you can find out angles x and y, as all triangles equal to 180 degrees