Question
I. 3x2 = 2x2 + 9x – 20
II. 3y2 = 75 In the following questions, two equations numbered I and II are given. You have to solve both the equations and give answer:Solution
I. 3x2 = 2x2 + 9x – 20 => x2 - 9x + 20 = 0 => x2 - 5x – 4x + 20 = 0 => x(x – 5) – 4(x – 5) = 0 => (x – 5) (x – 4) = 0 => x = 5, 4 II. 3y2 = 75 => y2 = 25 => y = -5, 5 Hence, x = y or the relationship cannot be established.
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