7.2 FACTORISING
You are going to learn how to factorise using the common factor. Factorising is the opposite of multiplying out brackets. You will need this to solve quadratic equations.
Learning objectives
At the end of this paragraph you are able to...
...simplify expressions.
...multiply out brackets.
...find the common factor.
...factorise with the use of the common factor.
Explanation video
Exercises
Do the exercises in your notebook, you need to copy them first. If you are done you need to check your answers with a different colour.
Exercise 1
Copy and fill in
a) h( 8m + ... ) = 8hm + 9h
b) a ( ... + ... ) = 2a2 + a
c) k ( ... - ... ) = 5k2 - 3k
Exercise 2
Copy and factorise.
a) 4a + 6b
b) 4p - pq
c) v2 + 18v
d) 2w - 6
e) pr + pq
f) y2 - 5y
g) 3m2 + 5m
h) 7kl - 20k
i) 8uv - 3v
j) 3rt + 9r
k) 12bc - 9c
l) 3z2 + 6z
Exercise 3
Factorise, put as many factors as possible outside the brackets.
a) 3b2 - 6a
b) 3mn - 3m
c) 3mn - 9mc
d) 12xyz - 16xy
e) 2bv + 8by
f) 5a2 - 15a3
Exercise 4
Factorise, put as many factors as possible outside the brackets.
a) 6v3 - 12v
b) 25g2 - 30g
c) 10c2 + 5c2w
d) 6f 4 - 3f 2
e) 18q2bc + 12qb2c
f) p4 - p3 + p2
g) 4h2y + hy - hy2
h) 2j8 + 18j6 - 16j5
i) 9j3s2l - 6js2l2