Expressing a solution in interval notation

I am faced with this problem. I am told to express the answer in interval notation.

|3x| > 12

I solve like usual, by doing this:

3x > 12 3x < -12
x > 4 x < -4

My problem is how would I express this in interval notation. I know that if it were x < 4 x > -4 it would be (-4, 4), but on a graph their solution sets point in opposite directions. I don't know where it starts or ends. Thank you for your time.

1 Answer

$x\in (-\infty,-4)\cup(4,+\infty)$ is a an option. It is a union of two disjoint intervals.

There is no way of writing it as one interval.