C/W Expanding Brackets 27 April 2005 Aim : To be able to expand brackets of the form (2x + 5)(4x + 2) Simplify: 5) 7a + 3a + 8 - 3 6) 6b + 5 + 3b - 1 7) y2 + 3y +4y + 7 8) 5x2 + 2x + 6x + 5 =10a + 5 =9b + 1 =y2 + 7y + 7 =5x2 + 8x + 5 1) 4x + x 2) 4t + t + 3 + 11 3) 5f + 6 + 7f + 13 4) 12 + 6g + 3g + 5 =5x =5t + 14 =12f + 19 =9g + 17
Expand Brackets Low C C B This means ‘get rid’ of the brackets in cases like: 3(x + 2) 4(2x + 3) x(x + 3) 3(x – 2) + 2(x – 3) (x + 3)(x – 2) Low C C B
(b + 4)(b + 2) b × b + 4 × 2 + b × 2 + 4 × b = b2 + 2b + 4b + 8 This can be written as: (b + 4)(b + 2) b × b + 4 × 2 + b × 2 + 4 × b = b2 + 2b + 4b + 8 = b2 + 6b + 8