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    E:\Working\Orange_Education\TouchPad_Maths_4\Open_Files\Chap_07\Chap_07
                     \ 10-Nov-2025  Bharat Arora   Proof-8                                    Reader’s Sign _______________________ Date __________

                    BASiCS of GeoMetRy

                    The word geometry is derived from the Greek words ‘geo’ meaning ‘Earth’ and ‘metro’
                    meaning ‘measurement’. Thus, the word ‘geometry’ means “Earth’s measurement”.
                    Let us go through some basics of geometry.

                                                             Basics of Geometry

                     Point               A point  shows an exact  position  or
                                         place. It looks like a dot. It has no length,
                                         breadth,  or height.  It  is  denoted  by  a
                                         capital letter, like Point A, Point B, Point
                                         C.

                     Line                A line is straight and goes on for ever in
                                         both directions. It has no endpoints. A
                                         line AB shown in the adjoining figure is
                                         denoted by   AB    or line m.

                     Line segment        A part of a line with two endpoints is
                                         called a line segment. A line segment
                                         AB  shown in the adjoining  figure is
                                         denoted by AB or BA.

                     Ray                 A part  of a line with one  endpoint  is
                                         called  a  ray. It  goes  on  endlessly  in
                                         one  direction.  A  ray  AB  shown in the
                                         adjoining  figure  is denoted  by  AB ,
                                         where A is its initial point.

                    Measuring a line Segment

                    We use a centimetre ruler (scale) to measure line segments. The length between two
                    consecutive numbers on this scale is 1 cm.

                                                                                                       FP

                    example 1. Measure the given line segment using a scale.
                                                         A            7 cm            B

                    Solution.                                                                                            FP

                    Step 1.  Place the scale along the line segment in such a way that one end of the line
                               segment coincides with the zero mark on the scale.

                                       A            7 cm            B
                                                                                                       FP

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                                                                                                    Geometry

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