Evaluate : (9a − 7b) (3a − B) - Mathematics

Evaluate : (9a − 7b) (3a − b)

Sum

(9a − 7b) (3a − b)

= 9a (3a − b) − 7b (3a − b)

= 27a² − 9ab − 21ab + 7b²

= 27a² − 30ab + 7b²

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Product of Sum and Difference of Two Terms

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Chapter 12: Identities - Exercise 12 (A) [Page 150]

Chapter 12 Identities
Exercise 12 (A) | Q 5.1 | Page 150

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