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

Last updated at August 14, 2026 by

Ex 9.5, 8 - Chapter 9 Class 8 Algebraic Expressions and Identities - Part 2

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Question 8 Using (𝑥+𝑎)(𝑥+𝑏)=𝑥^2+(𝑎+𝑏)𝑥+𝑎𝑏 , find (ii) 5.1 × 5.2 5.1 × 5.2 = (5+0.1)×(5+0.2) (𝑥+𝑎)(𝑥+𝑏)=𝑥^2+(𝑎+𝑏)𝑥+𝑎𝑏 Putting 𝑥 = 5 , 𝑎 = 0.1 & 𝑏 = 0.2 = (5)^2+(0.1+0.2)(5)+(0.1)(0.2) = 25+(0.3)5+(0.1×0.2) = 25+3/10×5+(1/10×2/10) = 25+(15/10)+2/100 = 25+1.5+0.02 = 𝟐𝟔.𝟓𝟐

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