Answer:
Option (D). 110°
Step-by-step explanation:
Since EB and AD are diameter,
[tex]m(\widehat{ECB})[/tex] = [tex]m(\widehat{ACD})[/tex] = 180°
[tex]m(\widehat{ECB})=m(\widehat{EDC})+m(\widehat{BC})[/tex] = 180° -------(1)
And [tex]m(\widehat{ACD})=m(\widehat{AB})+m(\widehat{BCD})[/tex]
180° = 40° + [tex]m(\widehat{BCD})[/tex]
[tex]m(\widehat{BCD})[/tex] = 140°
Since, [tex]m(\widehat{BCD})=m(\widehat{BC})+m(\widehat{CD})[/tex]
[tex]2m(\widehat{BC})[/tex] = 140° [Given [tex]m(\widehat{BC})=m(\widehat{CD})[/tex]]
[tex]m(\widehat{BC})[/tex] = 70°
From equation (1),
[tex]m(\widehat{EDC}})[/tex] = 180° - [tex]m(\widehat{BC})[/tex]
[tex]m(\widehat{EDC}})[/tex] = 180°- 70°
Therefore, measure of arc(EDC) = 110°
Option (D) will be the answer.
