standard_description: Prove theorems about triangles. Theorems include: measures of interior angles of a triangle sum to 180°; base angles of isosceles triangles are congruent; the segment joining midpoints of two sides of a triangle is parallel to the third side and half the length; the medians of a triangle meet at a point.
problem_activity: Line
$$AC$$
intersects line
$$EB$$
at point
$$F$$
. Ray
$$FD$$
extends from point
$$F$$
. Determine the measures of
$$\angle EFD$$
and
$$\angle CFD$$
.
[IMG]


aligns: no