Q13 of 168 Page 4

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

(i) (ii) Area () =

13.jpg


(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


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