Respuesta :

MamoonWasim

Step-by-step explanation:

DCF is 90°

so to find BCE

BCE+64+90=180

BCE=26°

CBE is (180-3x)

taking triangle BEC

(180-3x)+x+26=180

180-3x+x+26=180

-2x+26=0

-2x=-26

x=13