The measure of [tex]\angle AEC[/tex] is [tex]105^{o}[/tex].
What is vertically opposite angles?
Vertically opposite angles are the angles formed opposite each other when two lines intersect. Vertically opposite angles are always equal.
According to the given question.
We have a circle with center E and two chords CD and AB.
Also, both the chords intersecting each other and form vertical angles.
Here,
[tex]m\angle DEB = 105^{o}[/tex] (given)
Since, [tex]m\angle DEB[/tex] and [tex]m\angle AEC[/tex] are vertical opposite angles.
Therefore,
[tex]m\angle DEB = m\angle AEC[/tex]
[tex]\implies m\angle AEC = 105^{o}[/tex]
Hence, the measure of [tex]\angle AEC[/tex] is [tex]105^{o}[/tex].
Find out more information about vertical opposite angles here:
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