Question 173556
I assume you meant to type this

[y^2/(y - 4)] - [4/(y - 4)]

Treat this like you would a regular fraction.

Notice that the denominator is the same for both fractions.

In that case, we keep the denominator (y - 4) and subtract the numerators.

Doing that, this is what we get:

(y^2 - 4)/(y - 4)

Now, what can we do with the numerator (y^2 - 4)?  What does it look like?

We can say that (y^2 - 4) is the difference of two perfect squares and so it can and must be factored.


(y^2 - 4) factors out to be (y - 2) (y + 2)


Final answer:

[(y - 2)(y + 2)]/(y - 4)