# Ex 11.2, 2 - Chapter 11 Class 9 Constructions

Last updated at Oct. 5, 2018 by Teachoo

Last updated at Oct. 5, 2018 by Teachoo

Transcript

Ex 11.2, 2 Construct a triangle ABC in which BC = 8 cm, ∠B = 45° and AB − AC = 3.5 cm. Steps of Construction: Draw base BC of length 8 cm 2. Now, let’s draw ∠ B = 45° Let the ray be BX Check Ex 11.1, 2 on how to construct 45° Open the compass to length AB – AC = 3.5 cm. Note: Since AB – AC = 3.5 cm is positive So, BD will be above line BC From point B as center, cut an arc on ray BX. Let the arc intersect BX at D 4. Join CD Now, we will draw perpendicular bisector of CD 6. Mark point A where perpendicular bisector intersects BD Join AC ∴ Δ ABC is the required triangle

Constructing Triangle - Given base, angle and difference of sides

Chapter 11 Class 9 Constructions

Concept wise

- Constructing bisector of angle and perpendicular bisector
- Constructing angles - 60, 90, 45, 30 and others
- Constructing Triangle - Given base, angle and sum of other 2 sides
- Constructing Triangle - Given base, angle and difference of sides
- Constructing Triangle - Given sum of 3 sides and 2 base angles

About the Author

Davneet Singh

Davneet Singh is a graduate from Indian Institute of Technology, Kanpur. He has been teaching from the past 8 years. He provides courses for Maths and Science at Teachoo. You can check his NCERT Solutions from Class 6 to 12.