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