Question

Last question ! Is number 1 ---- D ?

Answer 1

The answer to question number one is A.

m Angle ACD = m Angle BAC (Opposite Interior Angle Theorem), m Angle ACD = z
So, m Angle BAC = z. Because 'x' is the value of the exterior angle of the leftmost triangle, the sum of the opposite angles ABD and BAC is equal to x. Thus, z + y = x (Answer A).