Q21 of 168 Page 5

If are equilateral triangles, where D is the mid point of BC, find the ratio of areas of .

21.jpg


ABC and BDE is an equilateral triangles


ABCDEF [By SAS]


By area of similar triangle theorem


Area() =AB2 [D is the midpoint of BC]


Area () BD2


=4BD2/BD2


=4/1


Area() = 4:1 Area ()


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