Selina Concise Class 6 Math Chapter 21 Fundamental Concepts Exercise 21A Solution
(1) State, true or false, correct the statement:
(i) False; Dot has no length and width.
(iii) False; The line segment PQ is only written as PQ.
(v) False; Three points are said to be collinear, if they lie in a straight line.
(2) Write how many lines can be drawn through:
(ii) Only one.
(iii) Only one.
(3) The shaded region of the given figure shows a plane:
(i) A, B and C
(ii) A, D and C
(iii) AC and DC
(b) State whether true or false:
(4) Correct the statement, if it is wrong:
(i) A ray can be extended infinitely on only one side of it
(ii) A ray has indefinite length
(iv) A line has no end-point
(5) State true or false, if false, give the correct statement:
(i) False; a line has an infinite number of points on it
(ii) False; an infinite number of lines can pass through a given point
(6) State whether the following pairs of lines or rays appear to be parallel or intersecting.
(7) Give two examples, from your surroundings, for each of the following:
(i) Tip of your pencil and tip of a nail
(ii) Lines printed on your note-book and edge of your table-top
(iii) Top of your study table a wall of your class-room
(iv) Surface of a cricket-ball and surface of your pen.
(8) Under what condition will two straight lines in the same plane have:
(9) Mark two points A and B on a page of your exercise book. Mark a third point P such that:
(10) Mark two points P and Q on a piece of paper. How many lines can you draw:
(i) Only one
(11) The adjoining figure shows a line AB. Draw figures to represent:
(12) The adjoining figure shows a ray AB. Draw figures to show:
(13) The adjoining figure shows a line segment AB. Draw figures to represent:
(14) Use a ruler and find whether following points are collinear or not:
(15) From the adjoining figure, write:
(i) EF ∕∕ GH, EF ∕∕ IJ and GH ∕∕ IJ
(ii) AB and CD
(iii) AB and GH