SOLUTION: In triangle ABC, DE is parallel to BC and AD = DE = BE. If BE is the angle bisector of angle CBA, then find the measure of angle ACB. Link to the graph: https://ibb.co/h9RJzZR

Algebra ->  Angles -> SOLUTION: In triangle ABC, DE is parallel to BC and AD = DE = BE. If BE is the angle bisector of angle CBA, then find the measure of angle ACB. Link to the graph: https://ibb.co/h9RJzZR      Log On


   



Question 1209478: In triangle ABC, DE is parallel to BC and AD = DE = BE.
If BE is the angle bisector of angle CBA, then find the measure of angle ACB.
Link to the graph: https://ibb.co/h9RJzZR

Answer by greenestamps(13200) About Me  (Show Source):
You can put this solution on YOUR website!


Since BE bisects angle CBA, let x be the measure of each of angles CBE and EBD.

In triangle DEB, DE = BE, so the measure of angle BDE is also x.

That makes the measure of angle EDA 180-x.

But DE and BC are parallel, so angles EDA and CBA are congruent.

2x = 180-x
3x = 180
x = 60

In triangle EDA, AD = DE, so angles DAE and DEA are congruent. Then, since the measure of angle EDA is 180-x=120, the measure of each of angles DAE and DEA is x/2 = 30.

And again DE and BC are parallel, so the measure of angle ACB is also 30.

ANSWER: 30 degrees