how do you work out 4(a+1)(a-8)

*reads your post again*

*deletes comment*

Multiplying 4 first would help him understand it better

Unless OP says otherwise, working out doesn't mean simplifying

Yeah I got fed up with school maths teachers so I taught myself.

Multiplying 4 first would help him understand it better

Unless OP says otherwise, working out doesn't mean simplifying

Until the OP says otherwise, working out doesn't mean solving.

Oh yes, I seem to miss the fact that you know the OP inside out and the nuances of what would help him understand better or not...

By definition, to work out is to solve, and to solve is to find x (a in this case)

i'm assuming you mean expand and simplify, if so you need to use foil.

this is a good technique for expanding as it gives you the answer in some quick steps. I will explain the method below.

foil-

4(a+1)(a-8) means you need to times the first brackets by 4.

Keep the numbers in the brackets ready to expand and simplify.

This will give you: (4a+4)(a-8)

you need to now times everything together (but in a certain way).

first
outer
inner
last

go in order so you multiply the first numbers together:
4a x a = 4a<sup>2

now the outer numbers:</sup>
4a x -8 = -32a

so far we have 4a² - 32a

next multiply the inner numbers, so:
4 x a = 4a

finally the last numbers:
4 x -8 = -32

if we put it all together we get: 4a² - 32a + 4a - 32

we now need to simplify this so we just put together the numbers that match.

4a² is the only squared number so we leave this as it is.

However, we have two lots of numbers that have 'a' after so we do -32a + 4a = -28a

32 is also the only alone number so we leave this as well.

Put this together and it equals: 4a² - 28a -32

simple when you know how don't hesitate to ask about anything else:u

please explain