Answer:
y=21; z=5
Step-by-step explanation:
The Isosceles Triangle Theorem says that if 2 sides of a triangle are congruent then the angles opposite will also be congruent. That means we can find the angle EFC by subtracting 69+69 from 180. (69+69)-180=42 Then we can divide this by 2 because we know that the 2 angles are congruent. 42/2=21.
To find z:
We can say that triangle EFD is congruent to CFD by SAS because angles EFD and CFD are congruent, DF is congruent to itself by the Reflexive prop. of Congruency, and because it is given that EF is congruent to CF. Using the CPCTC theorem we can say ED is congruent to CD which means z is 5.
