Last updated at May 29, 2018 by Teachoo

Transcript

Example 2 In figure , ray OS stands on a line POQ. Ray OR and ray OT are angle bisectors of ∠ POS and ∠ SOQ, respectively. If ∠ POS = x, find ∠ ROT. Given ∠ POS = x OR bisects ∠ POS So, ∠ROP = ∠ROS So, ∠ROP = ∠ROS = 1/2 (∠ POS) ∠ROP = ∠ROS = 𝑥/2 Now, ∠POS + ∠ SOQ = 180° x + ∠ SOQ = 180° ∠SOQ = 180° – x OT bisects ∠ SOQ So, ∠SOT = ∠TOQ So, ∠SOT = ∠TOQ = 1/2 (∠ SOQ) ∠SOT= ∠TOQ = 1/2 (180° – x) ∠SOT= ∠TOQ = 90° – 𝑥/2 Now, finding ∠ ROT ∠ ROT = ∠ ROS + ∠ SOT = 𝑥/2 + 90° – 𝑥/2 = 90°

Class 9

Important Questions for Exam - Class 9

- Chapter 1 Class 9 Number Systems
- Chapter 2 Class 9 Polynomials
- Chapter 3 Class 9 Coordinate Geometry
- Chapter 4 Class 9 Linear Equations in Two Variables
- Chapter 5 Class 9 Introduction to Euclid's Geometry
- Chapter 6 Class 9 Lines and Angles
- Chapter 7 Class 9 Triangles
- Chapter 8 Class 9 Quadrilaterals
- Chapter 9 Class 9 Areas of parallelograms and Triangles
- Chapter 10 Class 9 Circles
- Chapter 11 Class 9 Constructions
- Chapter 12 Class 9 Herons Formula
- Chapter 13 Class 9 Surface Areas and Volumes
- Chapter 14 Class 9 Statistics
- Chapter 15 Class 9 Probability

About the Author

Davneet Singh

Davneet Singh is a graduate from Indian Institute of Technology, Kanpur. He has been teaching from the past 9 years. He provides courses for Maths and Science at Teachoo.