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Question
One of the roots of equation kx2 – 10x + 3 = 0 is 3. Complete the following activity to find the value of k.
Activity:
One of the roots of equation kx2 – 10x + 3 = 0 is 3.
Putting x = `square` in the above equation
∴ `"k"(square)^2 - 10 xx square + 3` = 0
∴ `square` – 30 + 3 = 0
∴ 9k = `square`
∴ k = `square`
Solution
One of the roots of equation kx2 – 10x + 3 = 0 is 3.
Putting x = 3 in the above equation
∴ k(3)2 – 10 × 3 + 3 = 0
∴ 9k – 30 + 3 = 0
∴ 9k = 27
∴ k = `27/9` = 3
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