Quadrilateral

Different types of quadrilaterals
There are 5 types of quadrilaterals on the basis of their shape. These 5 quadrilaterals are:

Rectangle
Square
Parallelogram
Rhombus
Trapezium

Area and perimeter of a rectangle
If the length of the rectangle is L and breadth is B then,

Area of a rectangle = Length × Breadth or L × B
Perimeter of rectangle = 2 × (L + B)

Area and perimeter of a square
If the side of a square is ‘a’ then,

Area of the square = a × a = a²
Perimeter of the square = 2 × (a + a) = 4a

Area and perimeter of a parallelogram
If the length of a parallelogram is ‘l’, breadth is ‘b’ and height is ‘h’ then:

Perimeter of parallelogram= 2 × (l + b)
Area of the parallelogram = l × h

Area and perimeter of a rhombus
If the side of a rhombus is a then, perimeter of a rhombus = 4a

If the length of two diagonals of the rhombus is d1 and d2 then the area of a rhombus = ½ × d₁ × d₂

Area and perimeter of a trapezium
If the height of a trapezium is ‘h’ (as shown in the above diagram) then:

Perimeter of the trapezium= Sum of lengths of all the sides = AB + BC + CD + DA
Area of the trapezium = ½ × (Sum of lengths of parallel sides) × h = ½ × (AB + CD) × h

Theorem: Parallelograms on the same base and in between the same parallels are equal in area.
Here, area(ABCD) = area(ABEF)