Basic Geometrical Ideas - Solutions

 CBSE Class –VI Mathematics

NCERT Solutions
Chaper 4 
Basic Geometrical Ideas (Ex. 4.1)


Question 1. Use the figure to name:

(a) Five points

(b) A line

(c) Four rays

(d) Five line segments

Answer:  (a) Five points are: O, B, C, D, E

(b) A line: DE¯,DB¯,OE¯,OB¯

(c) Four rays: OD,OE,OC,OB

(d) Four line segments: DE¯,OE¯,OC¯,OB¯,OD¯

Question 2. Name the line given in all possible (twelve) ways, choosing only two letters at a time from the four given.

Answer: AB¯,AC¯,AD¯,BC¯,BD¯,CD¯,BA¯,CA¯,DA¯,CB¯,DB¯,DC¯

Question 3. Use the figure to name:

(a) Line containing point E.

(b) Line passing through A.

(c) Line on which O lies.

(d) Two pairs of intersecting lines.

Answer: (a) A line containing E = AE¯ or FE¯

(b) A line passing through A = AE¯ or DE¯

(c) A line on which O lies = CO¯ or OC¯

(d) Two pairs of intersecting lines are : AD¯,CO¯ and AE¯FE¯

Question 4. How many lines can pass though:

(a) one given point?

(b) two given points

Answer: (a) Infinite number of lines can pass through one given point.

(b) Only one line can pass through two given points.

Question 5. Draw a rough figure and label suitably in each of the following cases:

(a) Point P lies on AB¯.

(b) XY¯ and PQ¯ intersect at M.

(c) Line l contains E and F but not D.

(d) OP¯ and OQ¯ meet at O.

Answer:

Question 6. Consider the following figure of line MN¯. Say whether following statements are true or false in the context of the given figure:

(a) Q, M, O, N, P are points on the line MN¯.

(b) M, O, N are points on a line segment MN¯.

(c) M and N are end points of line segment MN¯.

(d) O and N are end points of line segment OP¯.

(e) M is one of the end points of line segment QO¯.

(f) M is point on ray OP.

(g) Ray OP is different from ray OP.

(h) Ray OPsame as ray OM..

(i) Ray OM. is not opposite to ray OP.

(j) O is not an initial point of NP¯ and NM¯.

Answer: (a) True, (b) True, (c) True, (d) False, (e) False, (f) False, (g) True, (h) False, (i) False, (j) False, (k) True