Question 4 (ii) - Algebra Identities and Formulas - Chapter 8 Class 8 Algebraic Expressions and Identities
Last updated at Dec. 16, 2024 by Teachoo
Algebra Identities and Formulas
Question 1 (i)
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Transcript
Question 4 Simplify. (ii) (2𝑥+5)^2−(2𝑥−5)^2 Solving (𝟐𝒙+𝟓)^𝟐 (𝑎+𝑏)^2=𝑎^2+𝑏^2+2𝑎𝑏 Putting 𝑎 = 2𝑥 & 𝑏 = 5 = (2𝑥)^2+(5)^2+2(2𝑥)(5) = 4𝑥^2+25+20𝑥 Solving (𝟐𝒙−𝟓)^𝟐 (𝑎−𝑏)^2=𝑎^2+𝑏^2−2𝑎𝑏 Putting 𝑎 = 2𝑥 & 𝑏 = 5 = (2𝑥)^2+(5)^2−2(2𝑥)(5) = 4𝑥^2+25−20𝑥 = 4𝑥^2+25+20𝑥−4𝑥^2−25+20𝑥 = (4𝑥^2−4𝑥^2 )+(25−25)+(20𝑥+20𝑥) = 0+0+40𝑥 = 𝟒𝟎𝒙
