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)
ADB
ACD
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
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