Question 6 (vii) - Algebra Identities and Formulas - Chapter 8 Class 8 Algebraic Expressions and Identities

Last updated at August 14, 2026 by

Ex 9.5, 6 - Chapter 9 Class 8 Algebraic Expressions and Identities - Part 8

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Question 6 Using identities, evaluate. (vii) 78 × 82 78 × 82 = (80−2)×(80+2) (𝑎−𝑏)(𝑎+𝑏)=𝑎^2−𝑏^2 Putting 𝑎 = 300 & 𝑏 = 3 = (80)^2−(2)^2 = 6400−4 = 𝟔𝟑𝟗𝟔

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