in order for the fraction to be > 0, the sign of the numerator must agree with the denominator, that is, if the numerator is positive, the denominator is positive as well, and if the numerator is negative, so is the denominator.

assume without loss of generality that both are positive (that means a similar thing happens if both are negative, so we don't have to consider that). so we have:

and

and

or and

so now, draw a number line and mark the values -2, 2 and 4. test all the regions between them and at the ends to see which region satisfies the original inequality