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PROPERTIES OF A RHOMBUS
                                                                                                                                   (i)    AB = BC = CD = DA.
        (i)    The opposite sides of a rhombus are parallel.                                                                       (ii)    A = B =C = D = 90°.
        (ii)    All the sides of a rhombus are equal.                                                                              (iii)    Diagonal AC = diagonal BD
        (iii)    The opposite angles of a rhombus are equal.
        (iv)   The diagonals of a rhombus bisect each other at right angles.                                                       6. KITE A quadrilateral which has two pairs of equal adjacent sides
                                                                                                                                                 but unequal opposite sides, ts called a kite.
        Thus, in a rhombus ABCD, we have:
        (i)    AB || DC and AD || BC.                                                                                                            In the given figure ABCD is a kite
        (ii)    AB = BC = CD = DA.                                                                                                               in which CB = CD and AB = AD
        (iii)   DAB = BCD and ABC = CDA.                                                                                                         but AD ≠ BC and AB ≠ CD.
        (iv)    Let the diagonals AC and BD intersect at 0.

        Then, OA = OC,                                                                                                                                                  PRACTICE EXERCISE 7.3
        OB = OD and AOB = COD = BOC = AOD = 1 right angle.
                                                                                                                                   1.Name the sides, vertices and angles of the given quadrilaterals
        4. RECTANGLE A parallelogram in which each angle is a right
        angle is called a rectangle.


        In the given figure, ABCD is a rectangle in which AB || DC,

        AD || BC and A = B = C = D = 90°.




        PROPERTIES OF A RECTANGLE

        (i)    Opposite sides of a rectangle are equal and parallel.
        (ii)    Each angle of a rectangle ts 90°•
        (iii)    Diagonals of a rectangle are equal..

        Thus, in a rectangle ABCD, we have:
        (i)    AB = DC, AD = BC and AB || DC, AD || BC.
        (ii)    A = B = C =  D = 1 right angle.
        (iii)    Diagonal AC = diagonal BD.                                                                                        Draw a quadrilateral. Name it AXYB. Draw its diagonals and name them.

        5. SQUARE A parallelogram in which all the sides are equal and each                                                        3. In the given figure, list the points that lie
        angle is a right angle, is called a square.                                                                                       a. in the interior of the quadrilateral PQRS.
        In the given figure, ABCD is a square in which AB = BC = CD = DA and                                                              b. in the exterior of the quadrilateral PQRS.
                                                                                                                                          c. on the boundary of the quadrilateral PQRS.
               A = B = C = D = 90°.

                                                                                                                                   4. Three angles of a quadrilateral measure 120° , 60° and 100° , respectively.
        PROPERTIES OF A SQUARE                                                                                                     Find the measure of the fourth angle.
        (i) The sides of a square are all equal.                                                                                   5. Draw two quadrilaterals to show the difference between a convex and a concave quadrilateral.
        (ii) Each angle of a square ts go0•
        (iii) The diagonals of a square are equal and bisect each other
        at right angles.

        Thus, in a square ABCD, we have:
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