ABCD is a parallelogram and e is the midpoint of BC show that area triangle DEC is equals to 1/4 area(ABCD)
Answers
Given that
⇒ ABCD is a parallelogram.
Kindly see the attachment also.
The diagonal BD divides the parallelogram ABCD in two equal triangles
Δ ABD and Δ BCD
Area of Δ ABD + Area of Δ BCD = Area of Prallelogram ABCD
(∵ Area of Δ ABD = Area of Δ BCD ) , so we have
Area of Δ BCD + Area of Δ BCD = Area of Prallelogram ABCD
2 (Area of Δ BCD ) = Area of Prallelogram ABCD .....(i)
Now E is the midpoint of BC , so DE divides Δ BCD into two equal triangles Δ BED & Δ DEC. So
Area of Δ BCD = Area of Δ BED + Area of Δ DEC
( ∵ Area of Δ BED = Area of Δ DEC ) , so
Area of Δ BCD = Area of Δ DEC + Area of Δ DEC
Area of Δ BCD = 2 (Area of Δ DEC) , putting this value in (i) , we get
2 [2(Area of Δ DEC )] = Area of Prallelogram ABCD
4(Area of Δ DEC ) = Area of Prallelogram ABCD
⇒ Area of Δ DEC = 1/4 (Area of Prallelogram ABCD)
Which is required.
I hope it will help you.
Step-by-step explanation: