In the triangle ABC, the bisector of the angle ABC intersects the bisector of the angle ACD at e, and the angle a is equal to 78 degrees

In the triangle ABC, the bisector of the angle ABC intersects the bisector of the angle ACD at e, and the angle a is equal to 78 degrees

You may have made a mistake. There won't be D in the triangle ABC. Even if there is a picture, there are many possibilities. I'll take D as B, if I don't forgive you~
A is 78 ° so angle B + angle c = 180-78 = 102 & nbsp;; because it is bisector, so ∠ 1 = 1 / 2 ∠ B & nbsp;,
Because of ∠ 2 = 1 / 2 ∠ C, so ∠ 1 + ∠ 2 = 1 / 2 (∠ B & nbsp; + ∠ C & nbsp;) = 51 ° and ∠ 1 + ∠ 2 + ∠ e = 180 °
Therefore, e = 129 degree