Step-by-step explanation:
sqrt(5x - 2) <= 3
5x - 2 <= 9
5x <= 11
x <= 11/5
but also : 5x -2 >= 0
otherwise the square root is not valid for real numbers.
5x >= 2
x >= 2/5
so the solution is for all x out of R (real numbers), where
2/5 <= x <= 11/5
