In rhombus ABCD, what is angle BCD?

Question

https://gmatclub.com/forum/download/file.php?id=28978 In rhombus ABCD, what is angle BCD? (1) BC = BD (2) Angle BDA = 60° 2016-01-17_2322.png

rachitbechem · Answer

Editing my post

IMO D. (I read Geometry rules and now understood Rhombus has equal sides)

With Statement 1: BC = BD hence it gives BC=BD=AD. Since all sides equal hence 60 deg. Therefore Sufficient

With Statement 2: angle BDA = 60 therefore angle DBC is also 60. Again since we got one angle and we know by rhombus property that BC = CD therefore all angles equal. Therefore Sufficient

chetan2u · Answer

Hi, 
boththe statements are suff alone..

With Statement 1: BC = BD hence it gives BC=BD=AD. all angles are 60 .. suff

With Statement 2: angle BDA = 60 , the diagonal bisects the angle so BCD= 60.. suff

rohit8865 · Answer

A rhombus has all sides equal..
1) if BC=BD then BCD is equilateral triangle and all angles are 60°
thus BCD=60°.....suff...
2) if Angle BDA = 60° then angle ABD is also 60° (As AD=AB)
thus making ABD equilateral triangle
As both triangles ABD & BCD of rhombus are SSS congruent then BCD=60°...suff

Ans D

devikeerthansr · Answer

D it is. Rhombus has equal sides. If the diagonal is equal to a side or if the angle at the diagonal is 60 then every angle in the triangles need to be 60

bumpbot · Answer

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In rhombus ABCD, what is angle BCD?

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