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Question
Find k if x = 3 is a root of equation kx2 – 10x + 3 = 0.
Solution
Given x = 3 is a root of equation kx2 – 10x + 3 = 0
So, x = 3 must satisfy the given quadration equation.
k(3)2 – 10(3) + 3 = 0
⇒ 9k - 30 + 3 = 0
⇒ 9k - 27 = 0
⇒ 9k = 27
⇒ k = `27/9`
⇒ k = 3
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