Page 120 - Maths Skill - 6
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118                                                                                                  Maths


        SQUARES AND RECTANGLES
        Basically a quadrilateral is a polygon with four line segments. In a quadrilateral ABCD :
             (i)  The four points A, B, C, D are called its vertices.                            A              D
            (ii)  The four line segments AB, BC, CD and DA are called the sides.

            (iii)  ∠A, ∠B, ∠C and ∠D are called its angles.
            (iv)  AC and BD are the two diagonals.                                             B                   C


        There are various examples of  quadrilateral like Rectangle, Square, Parallelogram, Rhombus etc.
        Rectangle and square are as follows:

        Rectangle
        A rectangle is quadrilateral with 4 right angles. In the figure given below PQRS is a rectangle.
        ∠P = ∠Q = ∠R = ∠S = 90°, PQ || RS and QR || PS. Here, PS and QR are called opposite sides. Similarly PQ and
        RS are opposite sides also.

                                                    P                  S






                                                    Q                  R

        Properties of Rectangle
        In a rectangle,
          1.  The opposite sides are parallel and equal.
          2.  All angles are right angles.

          3.  The diagonals are equal and besect each other.

        Square                                                                             A              D
        A  square  is  a  quadrilateral  with  four  equal  sides.  In  the  figure  given  aside,
        ABCD is a square in which ∠A = ∠B = ∠C = ∠D = 90° and AB = BC = CD = DA.


                                                                                           B              C


        Properties of Square
        In a square,                                              A                D

          1.  All the sides are equal.

          2.  All opposite sides are parallel.
          3.  All angles are right angles.
          4.  The diagonals form four isosceles right triangles.   B               C


        Beside this, if you rotate the square and rectangle, it does not change its properties i.e. same length and same
        angles. So, it concludes that rotated rectangle or square are still a rectangle or square.
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