Chapter 14: Factorisation

LHS = (y–3)² , which is similar to (a–b)² identity, where (a–b) ² = a²+b²-2ab

(y – 3)² = y²+(3) ²–2y×3 = y²+9 –6y ≠ y² – 9 = RHS

The correct statement is (y–3)² = y² + 9 – 6y

LHS = (z+5)² , which is similar to (a +b)² identity, where (a+b) ² = a²+b²+2ab

(z+5) ² = z²+5²+2×5×z = z²+25+10z ≠ z²+25 = RHS

The correct statement is (z+5) ² = z²+25+10z

LHS = (2a+3b)(a–b) = 2a(a–b)+3b(a–b)

= 2a²–2ab+3ab–3b²

= 2a²+ab–3b²

≠ 2a²–3b² = RHS

The correct statement is (2a +3b)(a –b) = 2a²+ab–3b²

LHS = (a+4)(a+2) = a(a+2)+4(a+2)

= a²+2a+4a+8

= a²+6a+8

≠ a²+8 = RHS

The correct statement is (a+4)(a+2) = a²+6a+8

LHS = (a–4)(a–2) = a(a–2)–4(a–2)

= a²–2a–4a+8

= a²–6a+8

≠ a²-8 = RHS

The correct statement is (a–4)(a–2) = a²–6a+8

LHS = 3x²/3x² = 1 ≠ 0 = RHS

The correct statement is 3x²/3x² = 1

LHS = (3x²+1)/3x² = (3x²/3x²)+(1/3x²) = 1+(1/3x²) ≠ 2 = RHS

The correct statement is (3x²+1)/3x² = 1+(1/3x²)

LHS = 3x/(3x+2) ≠ 1/2 = RHS

The correct statement is 3x/(3x+2) = 3x/(3x+2)

LHS = 3/(4x+3) ≠ 1/4x

The correct statement is 3/(4x+3) = 3/(4x+3)

LHS = (4x+5)/4x = 4x/4x + 5/4x = 1 + 5/4x ≠ 5 = RHS

The correct statement is (4x+5)/4x = 1 + (5/4x)

LHS = (7x+5)/5 = (7x/5)+ 5/5 = (7x/5)+1 ≠ 7x = RHS

The correct statement is (7x+5)/5 = (7x/5) +1