D is the midpoint of side BC of ∆ABC and E is the midpoint of BD. If O is the midpoint of AE, prove that ar(∆BOE) = ar(∆ABC).

Given : D is the midpoint of side BC of ∆ABC and E is the midpoint of BD and O is the midpoint of AE


To prove : ar(∆BOE) = ar(∆ABC)


Proof : Consider ∆ABC here D is the midpoint of BC


Area of (∆ABD) = Area of (∆ACD)


Area(∆ABD) = Area(∆ABC)—1


Now, consider ∆ABD here E is the midpoint of BD


Area of (∆ABE) = Area of (∆AED)


Area(∆ABE) = Area(∆ABD)—2


Substituting –1 in –2 , we get


Area(∆ABE) = ( Area(∆ABC))


Area(∆ABE) = Area(∆ABC)—3


Now consider ∆ABE here O is the midpoint of AE


Area of (∆BOE) = Area of (∆AOB)


Area(∆BOE) = Area(∆ABE)—4


Now, substitute –3 in –4 , we get


Area(∆BOE) = ( Area(∆ABC))


area(∆BOE) = area(∆ABC)


Hence proved


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