In a , AB = BC = CA = 2 a and . Prove that

(i) (ii) Area () =

(i) In ABD and ACD

ADB=ADC=90

AB=AC (given)

AD=AD (common)

ADBACD

BD=CD=a (By c.p.c.t)

In ADB

AD²+BD²=AB²

AD²+a²=(2a)²

AD²=4a²-a²

AD²=3a²

AD=a

(ii) Area of ABC=1/2xBCxAD

= 1/2x2axa

=3a²