How do you factor completely #x^2 + 2x – 15#?
To factorise, we firstly need two brackets, each containing an
This creates the
Now we need to get the rest of the terms. To do this, we need two factors of
The two factors that do this are
You can check by expanding it out.
When looking for factors, if it is not obvious straight away then list them out and you'll eventually get there.