Answer:
m∠ACE = 40°
Step-by-step explanation:
Consider the below figure attached with this question.
Given information: arc BD = 25°, minor arc AB = 115°, and minor arc DE = 115°.
We need to find the measure of ∠ACE.
minor arc AB + minor arc BD + minor arc DE + minor arc AE = 360°
115° + 25° + 115° + minor arc AE = 360°
255° + minor arc AE = 360°
minor arc AE = 360° - 255°
minor arc AE = 105°
The measure of minor arc AE is 105°.
Using Intersecting secants outside the circle theorem
Angle between two secants =
(Major arc - Minor arc)
![\angle ACE=\frac{1}{2}[Arc(AE)-Arc(BD)]](https://tex.z-dn.net/?f=%5Cangle%20ACE%3D%5Cfrac%7B1%7D%7B2%7D%5BArc%28AE%29-Arc%28BD%29%5D)
![\angle ACE=\frac{1}{2}[105-25]](https://tex.z-dn.net/?f=%5Cangle%20ACE%3D%5Cfrac%7B1%7D%7B2%7D%5B105-25%5D)
![\angle ACE=\frac{1}{2}[80]](https://tex.z-dn.net/?f=%5Cangle%20ACE%3D%5Cfrac%7B1%7D%7B2%7D%5B80%5D)
![\angle ACE=40](https://tex.z-dn.net/?f=%5Cangle%20ACE%3D40)
Therefore, the measure of ∠ACE is 40°.