Congruent isosceles triangles ABC and DEF with equal red edge lengths are placed on a plane as shown in the figure. Point A falls on edge [EF], point F falls on edge [BC], and edges [AC] and [DE] are parallel.
Accordingly, what is the measure of angle $x$ in degrees?
A) 44
B) 45
C) 46
D) 47
E) 48