Given : ABCF is a Rectangle
⇒ AB = CF
Given : AB = 6 cm
⇒ CF = 6 cm
Perimeter of a Rectangle is given by : 2(Length + Width)
Given : Perimeter of the Rectangle = 20 cm
⇒ 2(6 + BC) = 20
⇒ 6 + BC = 10
⇒ BC = 4
Given : BD = 9
But, We can See that : BD = BC + CD
⇒ CD + 4 = 9
⇒ CD = 5
We know that :
✿
Where : a and b are Lengths of Parallel Sides and Height is Length between those Parallel Sides
In the Given Trapezium :
The Parallel Sides are CD and EF and Height is CF
Given : EF = 3 cm