Please solve q 7?

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1 Answer
May 6, 2018

#BE=0#

Explanation:

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Given #AB=AC, AD# // #BC#, and #ADC# is equilateral,
#=> angleCAD=angleCDA=60^@#,
#=> angleACB=60^@, => DeltaABC# is also equilateral,
#=> AB=BC=AC=AD=DC#,
#=> ABCD# is a rhombus,
We know that the diagonals of a rhombus bisect opposite angles,
given that the bisector of #angleD# meets #AB# at #E#,
#=> E# coincides with #B#,
#=># the angle bisector is the diagonal #DB#,
#=> BE=0#