CHAPTER-4 BASIC GEOMETRICAL IDEAS
MATHEMATICS CLASS-6th NCERT BOOK SOLUTION IN ENGLISH
Mathematics NCERT Books Solution In HIndi PDF Free Download for Class 6th
There are many books in the market but “NCERT Books” stand alone in the market. Candidates preparing for civil services examinations as well as CBSE aspirants require good books and resources for high level preparation.
Here we are providing the facility to download Latest Edition (2020-21 Academic Year)MATHEMATICS NCERT Books,Solution And Notes HIndi & English totally free for class 6th students. You can download NCERT text-books as well as their solutions & Notes for Hindi & English medium schools.
There are many books in the market but “NCERT Books” stand alone in the market. Candidates preparing for civil services examinations as well as CBSE aspirants require good books and resources for high level preparation.
Here we are providing the facility to download Latest Edition (2020-21 Academic Year)MATHEMATICS NCERT Books,Solution And Notes HIndi & English totally free for class 6th students. You can download NCERT text-books as well as their solutions & Notes for Hindi & English medium schools.
[NCERT]*Mathematics NCERT Class 6th Books , Solution , Notes HIndi & English PDF Free Download
[NCERT]*Mathematics NCERT Class 6th Books IN English PDF Free Download
👉नोट:- लिंक पर क्लिक करें और पढ़े। 👈
MATHEMATICS NCERT CLASS 6th BOOK SOLUTION (CHAPTER WISE) ENGLISH
[NCERT]*Mathematics NCERT Class 6th SOLUTION IN ENGLISH : CHAPTER-3 PLAYING WITH NUMBER PDF Free Download
👉नोट:- लिंक पर क्लिक करें और पढ़े। 👈
👉THE ULTIMATE LEARNER👈
CHAPTER-4 BASIC GEOMETRICAL IDEAS
EXERCISE-4.1
1.Use the figure to name:
(a) Five points
ANS:) Five points are: O, B, C, D, E
(b) A line
ANS:) A line: DE, DB, OE, OB
(c) Four rays
ANS:) Four rays: OD, OE, OC, OB
(d) Five line segments
ANS:) Four line segments: DE, OE, OC, OB, , OD
2.Name the line given in all possible (twelve) ways, choosing only two letters at a time from the
four given.
ANS:) AB, AC, AD, BC, BD, CD, BA, CA, DA, CB, DB, DC
3. Use the figure to name: 
(a) Line containing point E.
ANS:) A line containing E = AE or FE
(b) Line passing through A.
ANS:) A line passing through A = AE or DE
(c) Line on which O lies.
ANS:) A line on which O lies = CO or OC
(d) Two pairs of intersecting lines.
ANS:) Two pairs of intersecting lines are : AD, CO and AE , FE
4. How many lines can pass though:
(a) one given point?
ANS:) Infinite number of lines can pass through one given point.
(b) two given points
ANS:) Only one line can pass through two given points.
5. Draw a rough figure and label suitably in each of the following cases:
(a) Point P lies on AB.
ANS:)
(b) XY and PQ intersect at M.
ANS:)
(c) Line l contains E and F but not D.
ANS:)
(d) OP and OQ meet at O.
ANS:)
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 .
ANS:) True
(b) M, O, N are points on a line segment MN .
ANS:) True
(c) M and N are end points of line segment MN .
ANS:) True
(d) O and N are end points of line segment OP .
ANS:) false
(e) M is one of the end points of line segment QO .
ANS:) false
(f) M is point on ray OP.
ANS:) false
(g) Ray OP is different from ray OP .
ANS:) True
(h) Ray OP same as ray OM.
ANS:) false
(i) Ray OM. is not opposite to ray OP.
ANS:) false
(j) O is not an initial point of NP and NM.
ANS:) false
[NCERT]*Mathematics NCERT Class 6th Books , Solution , Notes HIndi & English PDF Free Download
[NCERT]*Mathematics NCERT Class 6th Books IN English PDF Free Download
👉नोट:- लिंक पर क्लिक करें और पढ़े। 👈
MATHEMATICS NCERT CLASS 6th BOOK SOLUTION (CHAPTER WISE) ENGLISH
[NCERT]*Mathematics NCERT Class 6th SOLUTION IN ENGLISH : CHAPTER-3 PLAYING WITH NUMBER PDF Free Download
👉नोट:- लिंक पर क्लिक करें और पढ़े। 👈
👉THE ULTIMATE LEARNER👈
CHAPTER-4 BASIC GEOMETRICAL IDEAS
EXERCISE-4.2
1. Classify the following curves as (i) Open or (ii) Closed.
Ans:)
(a) Open curve
(b) Closed curve
(c) Open curve
(d) Closed curve
(e) Closed curve
2. Draw rough diagrams to illustrate the following:
(a) Open curve
Ans:)
(b) Closed curve
Ans:)
3. Draw any polygon and shade its interior.
Ans:)
4. Consider the given figure and answer the questions: 
(a) Is it a curve?
Ans:) Yes, it is a curve.
(b) Is it closed?
Ans:) Yes, it is closed.
5. Illustrate, if possible, each one of the following with a rough diagram:
(a) A closed curve that is not a polygon.
Ans:)
(b) An open curve made up entirely of line segments.
Ans:)
(c) A polygon with two sides.
Ans:) Polygon with two sides cannot be draw
[NCERT]*Mathematics NCERT Class 6th Books , Solution , Notes HIndi & English PDF Free Download
[NCERT]*Mathematics NCERT Class 6th Books IN English PDF Free Download
👉नोट:- लिंक पर क्लिक करें और पढ़े। 👈
MATHEMATICS NCERT CLASS 6th BOOK SOLUTION (CHAPTER WISE) ENGLISH
[NCERT]*Mathematics NCERT Class 6th SOLUTION IN ENGLISH : CHAPTER-3 PLAYING WITH NUMBER PDF Free Download
👉नोट:- लिंक पर क्लिक करें और पढ़े। 👈
👉THE ULTIMATE LEARNER👈
CHAPTER-4 BASIC GEOMETRICAL IDEAS
EXERCISE-4.3
1. Name the angles in the given figure:
Ans:) There are four angles in given figure:
∠ ABC, ∠ CDA, ∠ DAB, ∠ DCB
2. In the given diagram, name the point(s): 
(a) In the interior of ∠ DOE.
Ans:) Point interior of ∠ DOE : A
(b) In the exterior of ∠ EOF.
Ans:) Points exterior of ∠ EOF : C, A, D
(c) On ∠ EOF.
Ans:) Points on ∠ EOF : E, O, B, F
3. Draw rough diagrams of two angles such that they have:
(a) One point in common.
Ans:) 
(b) Two points in common.
Ans:) 
(c) Three points in common.
Ans:) 
(d) Four points in common.
Ans:) 
(e) One ray in common.
Ans:) 
👉नोट:- लिंक पर क्लिक करें और पढ़े। 👈
👉THE ULTIMATE LEARNER👈
CHAPTER-4 BASIC GEOMETRICAL IDEAS
EXERCISE-4.4
1. Draw a rough sketch of a triangle ABC. Mark a point P in its interior and a point Q in its
exterior. Is the point A in its exterior or in its interior?
Ans:)
A is neither interior of the figure nor exterior of triangle. It is a vertex.
2. 
(a) Identify three triangles in the figure:
Ans:) The three triangles are: ∆ABC, ∆ABD, ∆ADC
(b) Write the names of seven angles.
Ans:) Angles are: ∠ ADB, ∠ ADC, ∠ ABD, ∠ ACD, ∠ BAD, ∠ CAD, ∠ BAC
(c) Write the names of sic line segments.
Ans:) Line segments are: AB, AC, AD, BD, DC, BC
(d) Which two triangles have ∠ B as common?
Ans:) Triangles having common ∠ B: ∆ABC, ∆ABD,
👉नोट:- लिंक पर क्लिक करें और पढ़े। 👈
👉THE ULTIMATE LEARNER👈
CHAPTER-4 BASIC GEOMETRICAL IDEAS
EXERCISE-4.5
1. Draw a rough sketch of a quadrilateral PQRS. Draw its diagonals. Name them. Is the meeting
point of the diagonals in the interior or exterior of the quadrilateral?
Ans:)
Diagonal PR and diagonal SQ meet at O, which is inside the quadrilateral.
2. Draw a rough sketch of a quadrilateral KLMN. State: 
(a) Two pairs of opposite sides.
Ans:) Pair of opposite sides: KL and MN, KN and LM
(b) Two pairs of opposite angles.
Ans:) Pair of opposite angles: ∠ K and ∠ M, ∠ L and ∠ N
(c) Two pairs of adjacent sides.
Ans:) Pair of adjacent sides: KN and NM, KL and LM
(d) Two pairs of adjacent angles.
Ans:) Pair of adjacent angles: ∠ K and ∠ N, ∠ L and ∠ M
3. Investigate:
Use strip and fasteners to make a triangle and a quadrilateral.
Try to push inward at any one vertex of the triangle. Do the same to the quadrilateral.
Is the triangle distorted? Is the quadrilateral distorted? Is the triangle rigid?
Why is it that structures like electric towers make use of triangular shapes and not
quadrilateral?
Ans:) O is common to both the angles ∠ AOC and ∠ BOC.
No, the triangle is not distorted but the quadrilateral is distorted and also the triangle is rigid.
Structures like electric towers make use of triangular shape so that they could not be distorted
and they could be rigid.
👉नोट:- लिंक पर क्लिक करें और पढ़े। 👈
👉THE ULTIMATE LEARNER👈
CHAPTER-4 BASIC GEOMETRICAL IDEAS
EXERCISE-4.6
1. From the figure, identify: 
(a) The centre of circle.
Ans:) O is the centre.
(b) Three radii.
Ans:) Three radii: OA, OB and OC
(c) A diameter.
Ans:) A diameter: AC
(d) A chord.
Ans:) A chord: ED
(e) Two points in the interior.
Ans:) Interior points: O, P
(f) A point in the exterior.
Ans:) Exterior point: Q
(g) A sector.
Ans:) A sector: OAB
(h) A segment.
Ans:) A segment: ED
2. (a) Is every diameter of a circle also a chord?
Ans:) Yes, every diameter of a circle is also a chord.
2. (b) Is every chord of a circle also a diameter?
Ans:) No, every chord of a circle is not a diameter.
3. Draw any circle and mark:
(a) Its centre.
(b) A radius.
(c) A diameter.
(d) A sector.
Ans:)
4. Say true or false:
(a) Two diameters of a circle will necessarily intersect.
Ans:) True
(b) The centre of a circle is always in its interior.
Ans:) True