Answer
The solution set is $(-\displaystyle \infty,-\frac{2}{5} ]$
Work Step by Step
The idea is to isolate x on one side.
Adding, subtracting or multiplying/dividing with a positive number preserves order (the inequality symbol remains).
Multiplying/dividing with a negative number inverts the order (the inequality symbol changes).
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$ 8x-11 \leq 3x-13\qquad $ ... $/+11-3x $
$ 8x-3x \leq - 13+11$
$ 5x \leq -2\qquad $ ... $/\div 5$ (positive)
$ x \displaystyle \leq-\frac{2}{5}$
The solution set is $(-\displaystyle \infty,-\frac{2}{5} ]$
