Question

in the given figure side BC of ∆ABC is produced to form ray BD and CE||BA.Show that angle ACD =angleA+angleB.Reduce that angleA+angleB+angleC=180°​

Answer 1

Happy Propose Day Friends,

Good Night

The side BC of a triangle ABC is produced to D. The bisector of angle A meets BC in L. Prove that angle ABC + angle ACD = 2 angle ALC.

Triangle ABL.
Let angle BAL = a and angle LBA = b.
Exterior angle ALC = angle BAL + angle LBA
= a + b.

Triangle ABC.
As AL bisects angle BAC, angle LAC = a.
Exterior angle sum= 180