Check sibling questions

Example 4 - Chapter 7 Class 9 Triangles (Term 1)

Last updated at March 28, 2023 by

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

Get live Maths 1-on-1 Classs - Class 6 to 12

Book 30 minute class for ₹ 499 ₹ 299

Transcript

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

Ask a doubt
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 13 years. He provides courses for Maths, Science, Social Science, Physics, Chemistry, Computer Science at Teachoo.