a²-a = a(a-1)
Factorise fully is when brackets are involved in the equation
To factorise is to find the numbers that divide into the original number by only using prime numbers. For example factorise 20 = 2 times 2 times 5
to put into brackets
you do (245x)
It is: a(7a-8b)
It is the opposite of Expanding The Brackets
The answer will depend on where the brackets are. In general the solution would be to expand all the brackets, combine like terms and then factorise.