Question

In $\Delta$ ABC, DE is parallel to BC. Prove that area of ∆DOB= area of ∆EOC.

Answer 1

Area of ∆BEC and ∆BDC will be equal as they are on the same base and between same parallel.
Also, Area of ∆BEC - Area of ∆BOC = Area of ∆BDC - Area of ∆BOC.
Thus, Area of ∆DOB = Area of ∆EOC.