Answer:
DE = 62°
Step-by-step explanation:
An angle that lies outside a circle and whose sides are 2 secants of the circle is calculated using
∠DAE = 
(arcDE - arcBC ), that is
12 = 0.5 (DE - 38) ( multiply both sides by 2 )
24 = DE - 38 ( add 38 to both sides ), hence
DE = 62°
