angles and sides...

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angles and sides...

by rahulg83 » Sat Apr 25, 2009 11:51 am
i put D but answer given as A...
suggestions plz...
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by pakaskwa » Sat Apr 25, 2009 2:28 pm
IMO, A.

Stmt 1
AD=AC --> angle ADC=ACD --> angle ADE=ACB
and we know that angle EAD=BAC --> AED=ABC
So AB=AE. Stmt 1 SUFF.

Stmt 2
Let angle EAD=DAC=CAB=x
Since AC=CB --> angle ABC=CAB=x
--> angle ACB=180-ABC-CAB=180-2x
--> angle ACD=180-ACB=180-(180-2x)=2x
--> angle ADC=180-3x
--> angle ADE=3x
--> angle AED=180-4x

Only when AED=ABC (x=36) we can get AE=AB. Since we don't know value of x, stmt 2 NOT SUFF.

What's the OA?

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by rahulg83 » Sat Apr 25, 2009 9:59 pm
OA indeed is A, i deduced till finding ABC and AED in terms of x and without thinking twice, marked D assuming these terms are unequal.....how foolish of me !!!!
:x :evil: