Question 3 - Page 147 - Square of the Sum/Difference of Two Numbers - Chapter 6 Class 8 - We Distribute yet things Multiply (Ganita Prakash)

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Question 3 - Page 147 Expand the following using both Identity 1B and by applying the distributive property (i) (b – 6)2Now, (𝑏−6)^2 =𝑏^2−2 × 𝑏 × 6+6^2 =𝒃^𝟐−𝟏𝟐𝒃+𝟑𝟔 Question 3 - Page 147 Expand the following using both Identity 1B and by applying the distributive property (ii) (–2a + 3)2Now, (−2𝑎+3)^2 =(𝟑−𝟐𝒂)^𝟐 =3^2−2 × 3 × 2𝑎+〖(2𝑎) 〗^2 =𝟗^𝟐−𝟏𝟐𝒂+𝟒𝒂^𝟐 Question 3 - Page 147 Expand the following using both Identity 1B and by applying the distributive property (iii) ("7y" −3/4𝑧)^2Now, (𝟕𝒚−𝟑/𝟒𝒛)^𝟐 =〖(7𝑦)〗^2 − 2 × 7𝑦 ×3/4𝑧+(3/4𝑧)^2 =7^2 × 𝑦^2 − 2 × 7 ×3/4 × 𝑦/𝑧+3^2/(4^2 × 𝑧^2 ) =49𝑦^2 − (7 × 3)/2 × 𝑦/𝑧+9/(16 𝑧^2 ) =𝟒𝟗𝒚^𝟐 − 𝟐𝟏𝒚/𝟐𝒛+𝟗/(𝟏𝟔 𝒛^𝟐 )