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Ex 4.3, 2 (ii) - Chapter 4 Class 10 Quadratic Equations

Last updated at May 29, 2023 by

Ex 4.4, 2 - Chapter 4 Class 10 Quadratic Equations - Part 3

Ex 4.4, 2 - Chapter 4 Class 10 Quadratic Equations - Part 4

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Ex 4.3 ,2 Find the values of k for each of the following quadratic equations, so that they have two equal roots. (ii) kx (x – 2) + 6 = 0 kx (x – 2) + 6 = 0 kx2 – 2kx + 6 = 0 Comparing equation with ax2 + bx + c = 0 a = k, b = – 2k, c = 6 Since the equation has 2 equal roots D = 0 b2 – 4ac = 0 Putting values (–2k)2 – 4×𝑘×6=0 4k2 – 24k = 0 4k(k – 6) = 0 So, k = 0 & k = 6 For k = 0 , The equation becomes kx2 – 2kx + 6 = 0 0(x2) – 2(0)x + 6 = 0 0 – 0 + 6 = 0 6 = 0 Which is not correct So, k = 0 is not possible Therefore, k = 6

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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.