Areas of Parallelograms and Triangles

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The discussion revolves around proving various area relationships between two equilateral triangles, ABC and BDE, where D is the midpoint of BC and AE intersects BC at F. Key points include the need to show that the area of triangle BDE is one-fourth that of triangle ABC and half that of triangle BAE, among other area relationships. A hint suggests joining points E and C, and A and D, to demonstrate parallel lines which aid in the proof. The area formula for equilateral triangles is mentioned, emphasizing the relationship between the sides and their respective areas. The user confirms the correctness of their diagram and seeks further assistance in completing the proof.
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Homework Statement


ABC and BDE are two equilateral triangles such that D is the midpoint of BC. If AE intersects BC at F, show that :-
(i) ar(BDE) = 1/4 ar(ABC)
(ii) ar(BDE) = 1/2 ar(BAE)
(iii) ar(ABC) = 2ar(BEC)
(iv) ar(BFE) = ar(AFD)
(v) ar(BFE) = 2ar(FED)
(vi) ar(FED) = 1/2ar(AFC)


Homework Equations





The Attempt at a Solution


There was this hint :- [join EC and AD and then showing BE ll AC and DE ll AB,etc.]
 
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I couldn't upload the diagram.
I tried to follow the hint but from there on I couldn't succeed in solving this sum.
If anyone would tell me how to do this sum I'll be pleased
 
agnibho said:
ABC and BDE are two equilateral triangles such that D is the midpoint of BC. If AE intersects BC at F, show that :-
(i) ar(BDE) = 1/4 ar(ABC)
(ii) ar(BDE) = 1/2 ar(BAE)
(iii) ar(ABC) = 2ar(BEC)
(iv) ar(BFE) = ar(AFD)
(v) ar(BFE) = 2ar(FED)
(vi) ar(FED) = 1/2ar(AFC)

There was this hint :- [join EC and AD and then showing BE ll AC and DE ll AB,etc.]

My take on your diagram attached.
To continue, what is the formula for the area of an equilateral triangle?
 

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Area of an equilateral triangle = \sqrt{}3/4*side2
 
agnibho said:
Area of an equilateral triangle = \sqrt{}3/4*side2

I assume my diagram was correct?

Anyway, D is at the midpoint of BC, so BD = BC/2
Aabc = \sqrt{}3/4*BC2
Abde = \sqrt{}3/4*BD2 = \sqrt{}3/4*(BC/2)2

Finish that and retry the others.
 
Yes your diagram was correct
 
Thanks for your help.
 

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