Last updated at June 23, 2017 by Teachoo

Transcript

Example 5 Observe figure and then find ∠ P. Given: AB = 3.8 , PQ = 6√3 , BC = 6 , QR = 12 , AC = 3√3 , PR = 7.6 To find:- angle P i.e. ∠ P Solution:- in ∆ 𝐴𝐵𝐶 𝑎𝑛𝑑∆𝑅𝑄𝑃 Let us find the ratio of sides 𝐴𝐵/𝑅𝑄=3.8/7.6 = 38/76 = 1/2 𝐴𝐶/𝑅𝑃=(3√3)/(6√3)=1/2 𝐵𝐶/𝑄𝑃=6/12= 1/2 Thus, 𝐴𝐵/𝑅𝑄=𝐵𝐶/𝑄𝑃=𝐴𝐶/𝑅𝑃 (Using SSS similarity criterion) So , ∆ 𝐴𝐵𝐶 ~ ∆ 𝑅𝑄𝑃 Now we need to find ∠ P We know that corresponding angles of similar triangle are equal . Therefore, ∠ C = ∠ P In ∆ 𝐴𝐵𝐶 ∠ A + ∠ B + ∠ C = 180° 80°+60° + ∠ C = 180° 140° + ∠ C = 180° ∠ C = 180°−140° ∠ C = 40° Thus, ∠ C = 40° Hence , ∠ P = ∠ C = 40°

Example 5
Important
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Example 8 Important

Example 10 Important

Example 14 Important

Theorem 6.1 - Basic Proportionality Theorem Important

Theorem 6.7 Important

Ex 6.2, 4 Important

Ex 6.2, 5 Important

Ex 6.2, 6 Important

Ex 6.2, 9 Important

Ex 6.3, 11 Important

Ex 6.3, 12 Important

Ex 6.3, 13 Important

Ex 6.3, 14 Important

Ex 6.3, 15 Important

Ex 6.4, 1 Important

Ex 6.4, 3 Important

Ex 6.4, 5 Important

Ex 6.5, 2 Important

Ex 6.5, 3 Important

Ex 6.5, 8 Important

Ex 6.5, 11 Important

Ex 6.5, 12 Important

Ex 6.5, 15 Important

Class 10

Important Questions for Exam - Class 10

- Chapter 1 Class 10 Real Numbers
- Chapter 2 Class 10 Polynomials
- Chapter 3 Class 10 Pair of Linear Equations in Two Variables
- Chapter 4 Class 10 Quadratic Equations
- Chapter 5 Class 10 Arithmetic Progressions
- Chapter 6 Class 10 Triangles
- Chapter 7 Class 10 Coordinate Geometry
- Chapter 8 Class 10 Introduction to Trignometry
- Chapter 9 Class 10 Some Applications of Trignometry
- Chapter 10 Class 10 Circles
- Chapter 11 Class 10 Constructions
- Chapter 12 Class 10 Areas related to Circles
- Chapter 13 Class 10 Surface Areas and Volumes
- Chapter 14 Class 10 Statistics
- Chapter 15 Class 10 Probability

About the Author

Davneet Singh

Davneet Singh is a graduate from Indian Institute of Technology, Kanpur. He provides courses for Mathematics from Class 9 to 12. You can ask questions here.