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महाराष्ट्र राज्य शिक्षण मंडळएस.एस.सी (इंग्रजी माध्यम) इयत्ता १० वी

If one of the roots of quadratic equation x2 – kx – 15 = 0 is – 3, then find the value of ‘k’ - Algebra

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प्रश्न

If one of the roots of quadratic equation x2 – kx – 15 = 0 is – 3, then find the value of ‘k’

बेरीज

उत्तर

– 3 is one of the roots of the equation x2 – kx – 15 = 0.

Putting x = – 3 in the given equation, we get

(– 3)2 – k(– 3) – 15 = 0

∴ 9 + 3k – 15 = 0

∴ 3k – 6 = 0

∴ 3k = 6

∴ k = `6/3`

∴ k = 2

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  या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?
पाठ 2: Quadratic Equations - Q.2 (B)

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