we have
[tex]\frac{x}{4}\leq\text{ }\frac{9}{x}[/tex]
Multiply in cross
[tex]x^2\leq36[/tex]
square root both sides
[tex](\pm)x\leq6[/tex]
see the attached figure to better understand the problem
the solution is the interval {-6,6}
the solution in the number line is the shaded area at right of x=-6 (close circle) and the shaded area at left of x=6 (close circle)
