Factorise: A2 - 23a + 42

factorise: a² - 23a + 42

Sum

a² - 23a + 42 ...[42 = 21 × 2 and 21 + 2 = 23]

= a² - 21a - 2a + 42

= a(a - 21) - 2(a - 21)

= (a - 21)(a - 2)

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Factorisation by Grouping

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Chapter 13: Factorisation - Exercise 13 (F) [Page 163]

Chapter 13 Factorisation
Exercise 13 (F) | Q 4.1 | Page 163

Factorise by the grouping method : (ax + by)² + (bx - ay)²

Factorise : a³ -a² +a -1

Factorise : (a² − b²) c + (b² − c²)a

factorise: x² - 10xy + 24y²

factorise: 1 − (2x + 3y) − 6(2x + 3y)²

factorise: 8 + 6(a + b) - 5(a + b)²

Factorise: 2(x + 2y)² − 5(x + 2y) + 2

factorise: 3a²x - bx + 3a² - b

Factorise the following by grouping the terms:
15x² + 7y - 3x - 35xy

Factorise the following by grouping the terms:

`"p"^2 + (1)/"p"^2 - 2 - 5"p" + (5)/"p"`