NCERT Solutions for Class 6 Maths Chapter 5 Understanding Elementary Shapes Ex 5.6

Ncert Solutions Chapter 5 Understanding Elementary Shapes Ex 5.6 Ncert Solutions For Class 6 Maths Chapter 5 Exercise 5.6 Ncert Solutions Class 6 Maths Chapter 5 Exercise 5.6 Ncert Class 6 Maths Chapter 5 Exercise 5.6 Class 6 Maths Ch 5 Ex 5.6 Ncert Maths Class 6 Chapter 5 Exercise 5.6

NCERT Solutions for Class 6 Maths Chapter 5 Understanding Elementary Shapes Ex 5.6

Question 1.
Name the types of following triangles:
(a) Triangle with lengths of sides 7 cm, 8 cm and 9 cm.
(b) ΔABC with AB = 8.7cm, AC =7cm andBC = 6 cm.
(c) ΔPQR such that PQ = QR = PR = 5 cm.
(d) ΔDEF with m ∠D = 90°.
(e) ΔXYZ with m ∠Y = 90° and XY = YZ.
(f) ΔLMN with m ∠L = 30°, m ∠M =70° and m ∠N = 80°.
Solution :
(a) Scalene triangle
(b) Scalene triangle
(c) Equilateral triangle
(d) Right angled triangle
(e) Isosceles right triangle
(f) Acute angled triangle.

Question 2.
Match the following :

Measures of triangle	Type triangle
(i) 3 sides of equal length	(a) Scalene
(ii) 2 sides of equal length	(b) Isosceles right angled
(iii) All sides are of different length	(c) Obtuse angled
(iv) 3 acute angles	(d) Right angled
(v) 1 right angle	(e) Equilateral
(vi) 1 obtuse angle	(f) Acute-angled
(vii) 1 right angle with two sides of equal length	(g) Isosceles

Solution :

Measures of triangle	Type triangle
(i) 3 sides of equal length	(e) Equilateral
(ii) 2 sides of equal length	(g) Isosceles
(iii) All sides are of different length	(a) Scalene
(iv) 3 acute angles	(f) Acute-angled
(v) 1 right angle	(d) Right angled
(vi) 1 obtuse angle	(c) Obtuse angled
(vii) 1 right angle with two sides of equal length	(b) Isosceles right angled

Question 3.
Name each of the following triangles in two different ways : (you may judge the nature of the angle by observation).


Solution :
(a) Acute-angled and isosceles.
(b) Right-angled and scalene.
(c) Obtuse-angled and isosceles.
(d) Right-angled and isosceles.
(e) Equilateral and acute-angled.
(f) Obtuse-angled and scalene.

Question 4.
Try to construct triangles using matchsticks. Some are shown here. Can you make a triangle with

(a) 3 matchsticks?
(b) 4 matchsticks?
(c) 5 matchsticks?
(d) 6 matchsticks?
(Remember you have to use all the available matchsticks in each case). Name the type of triangle in each case. If you cannot make a triangle, think of reasons for it.
Solution :
(a) Yes, an equilateral triangle.
(b) No, since the sum of the lengths of any two sides of a triangle is always greater than the length of the third side.
(c) Yes, an isosceles triangle.
(d) Yes, an equilateral triangle.

Question 1

Identify the type of angle: 35°

Solution

Since:

35∘<90∘35^\circ < 90^\circ35∘<90∘

It is an acute angle.

Answer:

$AcuteAngle$

Question 2

Identify the type of angle: 90°

Solution

θ=90∘\theta = 90^\circθ=90∘

It is a right angle.

Answer:

$RightAngle$

Question 3

Identify the type of angle: 150°

Solution

Since:

90∘<150∘<180∘90^\circ < 150^\circ < 180^\circ90∘<150∘<180∘

It is an obtuse angle.

Answer:

$ObtuseAngle$

Question 4

Identify the type of angle: 180°

Solution

180∘180^\circ180∘

It is a straight angle.

Answer:

$StraightAngle$

Question 5

Which is greater: 60° or 100°?

Solution

100∘>60∘100^\circ > 60^\circ100∘>60∘

Answer:

100∘100^\circ100∘