Find the roots of the following quadratic equations by factorisation: x2 – 3x – 10 = 0 - Mathematics

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Sum

Find the roots of the following quadratic equations by factorisation:

x2 – 3x – 10 = 0

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Solution

x2 – 3x – 10

= x2 - 5x + 2x - 10

= x(x - 5) + 2(x - 5)

= (x - 5)(x + 2)

Roots of this equation are the values for which (x - 5)(x + 2) = 0

∴ x - 5 = 0 or x + 2 = 0

⇒ x = 5 or x = -2

  Is there an error in this question or solution?
Chapter 4: Quadratic Equations - Exercise 4.2 [Page 76]

APPEARS IN

NCERT Mathematics Class 10
Chapter 4 Quadratic Equations
Exercise 4.2 | Q 1.1 | Page 76

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