Question

It's very important for me. Please say quickly​

Answer 1

Given ABCD is a trapezium in which AC and BD are diagonals.

Again given AB || DC and diagonals AC and BD intersect at a point O.

We have to prove that

area (Δ AOD) = area (Δ BOC).

from the figure,

Δ ABD and Δ ABC has the same base AB and between the same parallels AB and DC.

So area (Δ ABD) = area (Δ ABC)

Subtract area (Δ AOB) on both side

area (Δ ABD) - area (Δ AOB) = area (Δ ABC) - area (Δ AOB)

=> area (Δ AOD) = area (Δ BOC)

Answer 2

Answer:

Proved area of Δ AOD = area of Δ BOC

Step-by-step explanation:

AB ║CD

if we draw ⊥ from D & C at AB

DE ⊥ AB  & CF ⊥ AB

DE = CF  as AB ║CD

Area of Δ ABD  = (1/2) * Base * Height

Area of Δ ABD  = (1/2) (AB) DE

Area of Δ ABC  = (1/2) (AB) CF

DE = CF

Area of Δ ABD  = Area of Δ ABC

Area of Δ ABD = Area of Δ AOB + area of Δ AOD

Area of Δ ABC = Area of Δ AOB + area of Δ BOC

Area of Δ AOB + area of Δ AOD = Area of Δ AOB + area of Δ BOC

Cancelling Area of Δ AOB from both sides

area of Δ AOD = area of Δ BOC

QED