How do you factor the expression #4x^2 + 16x + 15#?
I'm going to explain this using the most common method of factorising: by splitting the middle term.
The first step is to multiply the coefficient of
Now, we need to find the pair of factors of
With a quick glance, it's clear that the sum of the factors in the pair
Great! So now we split the coefficient of middle term
Note: It doesn't matter if you reverse the order and split
Now, we must take out common factors from the first two terms and then the next two terms:
Now, we can take
and voila, that's the factored expression!