|5x-4| > 16
The |5x-4| is the modulus of (5x - 4), so we will look at two cases where (5x - 4) is positive and negative.
Positive
(5x - 4) > 16
5x > 16 + 4
5x > 20
x > 20/5
x > 4
Negative case
-(5x - 4) > 16
Divide both sides by -1 and the sign reverses.
(5x - 4) < 16/-1
5x - 4 < -16
5x < -16 + 4
5x < 4 - 16
5x < -12
x < -12/5
x < -2.4
So the solutions are x > 4 and x < -2.4
Combining both solutions: -2.4 > x > 4
Hope this explains it.
