Check sibling questions

Example 4 - In Triangle ABC, the bisector AD of Angle A is perpendicular to side BC. - Examples

Example 4 - Chapter 7 Class 9 Triangles - Part 2

This video is only available for Teachoo black users

Solve all your doubts with Teachoo Black (new monthly pack available now!)


Given: AD is bisector of ∠ A So, ∠ BAD = ∠ CAD Also, AD is perpendicular to BC So, ∠ ADB = ∠ ADC = 90° To prove: AB = AC & Δ ABC is isosceles Proof: In ΔABD and ΔACD, ∠ BAD = ∠ CAD AD = AD ∠ ADB = ∠ ADC So, Δ ABD ≅ Δ ACD So, AB = AC Since 2 sides of triangle are equal Δ ABC is an isosceles triangle

Davneet Singh's photo - Co-founder, Teachoo

Made by

Davneet Singh

Davneet Singh has done his B.Tech from Indian Institute of Technology, Kanpur. He has been teaching from the past 12 years. He provides courses for Maths, Science, Social Science, Physics, Chemistry, Computer Science at Teachoo.