5) Squarea) Square is a rectangle with Length = Breadthb) Area of a Square = (side)^{2} = (1/2)(Diagonal)^{2} c) Diagonal = √side d) Perimeter of a square = 4(side) e) Diagonals of a square bisect each other at right angles. 6) Parallelograma) Opposite sides of a parallelogram are equal in length and are parallel to each other.b) Diagonal of a parallelogram bisect each other and divide it into two triangles of equal areas. c) Area of a parallelogram = Base x Height 7) Rhombusa) Area of a rhombus = (1/2)(Product of diagonals)b) Sides of a rhombus are equal. c) Perimeter of a rhombus = 4(side) d) Diagonals of a rhombus are unequal and bisect each other at right angles. 8) Trapeziuma) Area of a Trapezium = (1/2)(Sum of parallel sides)(Distance between parallel sides)9) Other important formulasa) Area of 4 walls of a room = 2(Length + Breadth)Heightb) A parallelogram and a rectangle on the same base and between same parallel sides are equal in area. |