27 April 2005C/W Expanding Brackets

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

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

=10a + 5

=9b + 1

=y2 + 7y + 7

=5x2 + 8x + 5

Expand Brackets

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)This can be written as:

b × b + b × 2 + 4 × b + 4 × 2

= b2 + 2b + 4b + 8

= b2 + 6b + 8