Ncert Solutions For Class 6 Maths Ex 5.6

Ncert Solutions For Class 6 Maths Chapter 5 Ex 5.6

Question 1:

Name the triangles types given below-:

(i) Triangle with lengths of sides 8.7 cm, 7 cm and 6 cm.

(ii) \(\Delta PQR\) with PQ = 9cm, PR = 8cm and QR = 7cm.

(iii) \(\Delta ABC\) such that AB= BC = AC = 6 cm.

(iv) \(\Delta XYZ\:with\:n\angle X=90^{\circ}\)

(v) \(\Delta DEF\:with\:n\angle E=90^{\circ}\) and DE = EF

(vi) \(\Delta KLM\:with\:n\angle K=30^{\circ},\:n\angle L=70^{\circ}\:and\:n\angle M=80^{\circ}\)

Answer:

(i) Scalene triangle

(ii) Scalene triangle

(iii) Equilateral triangle

(iv)Right-angled triangle

(v) Isosceles right-angled triangle

(vi Acute-angled triangle

 

Question 2:

Match the following-:

Measure of Triangle Types of Triangle

(a) 2 sides having equal length (i) Isosceles right angle

(b) 3 sides having equal length (ii) Right angle

(c) 1 right angle (iii) Scalene

(d) 3 acute angles (iv) Equilateral

(e) All the sides with different length (v) Obtuse angle

(f) 1 right angle having two sides of equal length (vi) Acute angle

(g) 1 obtuse angle (vii) Isosceles

Answer:

(a) 2 sides having equal length => (vii) Isosceles

(b) 3 sides having equal length => (iv) Equilateral

(c) 1 right angle => (ii) Right angle

(d) 2 acute angles => (vi) Acute angle

(e) All the sides with different length => (iii) Scalene

(f) 1 right angle having two sides of equal length => (i) isosceles right angle

(g) 1 obtuse angle => (v) Obtuse angle

Question 3:

Given below are the triangles, Name them in two different ways-:

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Answer:

(i) Isosceles triangle and Acute angled triangle

(ii) Scalene triangle and Right-angled triangle

(iii) Isosceles triangle and Obtuse-angled triangle

(iv)Isosceles triangle and Right-angled triangle

(v) Acute angled triangle and Equilateral triangle

(vi)Scalene triangle and Obtuse-angled triangle

 

Question 4:

Try out constructing triangles by using matchsticks as shown below.

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Can a triangle be made using-:

(i) 3 matchsticks

(ii) 4matchsticks

(iii) 5 matchsticks

(iv) 6 matchsticks

(All the available matchsticks are to be used in each case)

If a triangle is not formed, then try to give specific reasons for that.

Answer:

(i) For 3 matchsticks

An acute angle triangle is formed with 3 matchsticks because the sum of the two sides is greater than the third side.

(ii) For 4 matchsticks

By using 4 matchsticks a square is formed, so therefore it is not possible in this case.

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(iii) For 5 matchsticks

An acute angle triangle is formed with the help of 5 matchsticks because in this case the sum of the two sides is greater than the third side.

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(iv) For 6 matchsticks

An acute angle triangle is formed with the help of 6 matchsticks because in this case the sum of the two sides is greater than the third side.

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