Example 3 - Chapter 10 Class 11 Conic Sections
Last updated at Dec. 16, 2024 by Teachoo
Last updated at Dec. 16, 2024 by Teachoo
Example 3 Find the centre and the radius of the circle x2 + y2 + 8x + 10y – 8 = 0 Given x2 + y2 + 8x + 10y − 8 = 0 We need to make this in form (x – h)2 + (y – k)2 = r2 From (1) x2 + y2 + 8x + 10y − 8 = 0 (x2 + 8x) + (y2 + 10y) = 8 (x)2 + 2(4)(x) + y2 + 2(5)(y) = 8 [x2 + 2(4)(x) + (4)2 − (4)2] + [y2 + 2(5)(y) + (5)2 − (5)2] = 8 [x2 + 2(4)(x) + (4)2] + [y2 + 2(5)(y) + (5)2] − (4)2 − (5)2 = 8 (x + 4)2 + (y + 5)2 = 8 + 16 + 25 (x + 4)2 + (y + 5)2 = 49 (x – (– 4))2 + (y – (–5))2 = 72 Comparing (2) with (x – h)2 + (y – k)2 = r2 h = −4 , k = − 5 & r = 7 Thus, centre of circle = (h, k) = (−4, −5) & Radius = r = 7
Examples
Example 2
Example 3 Important You are here
Example 4 Important
Example 5
Example 6 Important
Example 7 Important
Example 8 Important
Example 9
Example 10 Important
Example, 11
Example 12 Important
Example 13 Important
Example 14 (i)
Example 14 (ii) Important
Example 15
Example 16 Important
Example 17
Example 18 Important
Example, 19 Important
About the Author
Davneet Singh has done his B.Tech from Indian Institute of Technology, Kanpur. He has been teaching from the past 14 years. He provides courses for Maths, Science and Computer Science at Teachoo