Question

In figure, D is the mid-point of side
BC of a ∆ABC and ∆ABD = 50°. If
AD = BD = CD, then find the
measure of ZACD. ​

Answer 1

Answer:

In △ABC, we have

AB=AC⇒∠ABC=∠ACB

(angles opposite to equal sides.)

Again in △DBC, we have

DB=DC ......... (given)

⇒∠DBC=∠DCB (angles opposite to equal sides).

Hence we obtain

∠ABC−∠DBC=∠ACB−∠DCB.

This gives

∠ABD=∠ACD. [henceproved]