Answer:

Step-by-step explanation:
Given that;

then triangle ABC is an isosceles triangle;

From the given figure, we can observe that quadrilateral ADFE is a parallelogram.
Recall that opposite angles of a parallelogram are equal.
So, we have;

Also, the same rule applies to parallelogram BFDE and CDEF;
So, we have;


Therefore, we have;
