Question

In Δ ABC, side AB is produced to D so that BD = BC. If ∠B = 60° and ∠A = 70°, prove that :
(i) AD > CD (ii) AD>AC

Answer 1

It is given that

, and

We have to prove that

(1)

(2)

(1)

Now

And since BD=BC, so, and

That is,

Now

And, so

Hence (1) (Side in front of greater angle will be longer)

And (2) Proved.