Chapter - 5 Understanding Elementary Shapes

Q&A -Ask Doubts and Get Answers

Q
Understanding Elementary Shapes

Question:

1. Name the types of following triangles :

(a) Triangle with lengths of sides 7 cm, 8 cm and 9 cm.

(b) โˆ†ABC with AB = 8.7 cm, AC = 7 cm and BC = 6 cm.

(c) โˆ†PQR such that PQ = QR = PR = 5 cm.

(d) โˆ†DEF with m∠D = 90°

(e) โˆ†XYZ with m∠Y = 90° and XY = YZ.

(f) โˆ†LMN 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) Right angled Iscosceles Triangle.

(f) Acute angled Triangle.

 

2. Match the following :

Measures of Triangle Type of 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:

(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

 

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 triangle.

(b) Right angled and scalene triangle.

(c) Obtuse angled and isosceles triangle.

(d) Right angled and isosceles triangle.

(e) Acute angled and equilateral triangle.

(f) Obtuse angles and scalene triangle.

 

4. Try to construct triangles using match sticks. 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, we can make a triangle with 3 matchsticks.

The triangle formed is an equilateral triangle.

(b) No, a triangle with 4 matchsticks is not possible as the sum of two small sides is equal to the 3rd side in this case, which is not true for a triangle.

(c) Yes, we can make a triangle with 5 matchsticks.

The triangle formed is an isosceles triangle.

(d) Yes, we can make a triangle with 6 matchsticks.

The triangle formed is an equilateral triangle.

 

 

 

Answer:


Related Questions for Study

What our students and parents say about us!

Choose EduSakshamยฎ
Embrace Better Learning

edusaksham-mobile-app