Page 89 - Maths Skill - 6
P. 89

Lines and Angles                                                                                        87



                                                    Exercise 6.1


          1.  Fill in the blanks.

             (i)  A dot gives us the idea of a ___________.
            (ii)  A tabletop gives an idea of a ___________.
            (iii)  Two lines lying in a plane are ___________ if they do not intersect each other.

            (iv)  Five points are ___________ if they all lie on a line.
                                                                                                       D
          2.  Write the name of all the points, line segments and planes in the given figure.                     C

          3.  How many lines can be drawn through a point?                                      A           B
          4.  How many lines can be drawn through two given distinct points?
                                                                                                        H         G
          5.  Name all the line segments in each of the following figures.
                                                                                                  E        F



             (i)                              (ii)                            (iii)










            (iv)                              (v)                             (vi)







        ANGLES
        Look at the pictures given below of some physical objects that we often encounter in our day-to-day life.













                                Clock               Divider             Scissors            Forceps

                                            Fig. 6.6
        Here, we could notice one common thing that both the arms of each picture are
        hinged at a point, such that they are inclined towards each other and have an
        opening   between them. Thus, we can say that these arms form an angle at a point
        of their joint.
        An angle is a figure formed by two different rays starting from the same initial
        point. The common starting point of the two rays is called vertex of the angle and
        the two rays are known as its arms or sides as shown in Fig. 6.7.                           Fig. 6.7
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