Use suitable identities to find the following products :- (x + 8) (x – 10) - Mathematics

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Use suitable identities to find the following products :- (x + 8) (x – 10)

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Solution

By using the identity (x + a)(x + b) = x2 + (a + b)x ab,

(x + 8)(x - 10) = x2 + (8 - 10)x (8)(-10)

                      = x2 - 2x - 80

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Chapter 2: Polynomials - Exercise 2.5 [Page 48]

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NCERT Mathematics Class 9
Chapter 2 Polynomials
Exercise 2.5 | Q 1.2 | Page 48

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