[tex]\large{\rm{\underline{\underline{Answer:}}}}[/tex]
Angle AEB and Angle DEC are opposite angles which means they are equal in measure. Hence,
⇛ Angle AEB = Angle DEC
⇛ 9x + 8° = 3x + 42°
⇛ 9x - 3x = 42° - 8°
⇛ 6x = 34°
⇛ x = (34/6)°
To find: Angle DEC = 3(
34/6 °) + 42° = 59° (Ans)
