Question

Q.25 which is mentioned in the question ppr plz..

Answer 1

use phythgors theorm

Answer 2

Given 
$BC^{2} = AC* CD$
∴ BC * BC = AC * CD
∴$\frac{BC}{CD}= \frac{AC}{BC}$
∠ACB = ∠BCD

So,
ΔABC ≈ ΔBDC .....by SAS test of similarity.

So,
[tex] \frac{AB}{BD}= \frac{BC}{CD}= \frac{AC}{BC} [/tex]
BY CPST,

So,
$\frac{AB}{BD}= \frac{AC}{BC}$

Now,
AB =  AC since the triangle is an isosceles triangle,

Thus,
$\frac{1}{BD}= \frac{1}{BC}$

∴BD =BC

This is the proof for the first answer.