Math Help - Factorisation

1. Factorisation

Hi,

I'm really stuck on factorisation, the question I have to answer is, 'Factorise 5x+15'.

Any help would be appreciated

2. Originally Posted by nathank93
Hi,

I'm really stuck on factorisation, the question I have to answer is, 'Factorise 5x+15'.

Any help would be appreciated
you should know that 15=3*5

so 5x+15 = 5x+3*5

Now you notice there is a 5 in both terms, so we can write it like this
5(x)+5(3)

Now we can pull it out of both
5(x+3)

And of course, you can check this by seeing that the 5 will be distributed to each element within the parentheses. Factoring is basically "undistributing."

So 5x+15 = 5(x+3)