Answer:
[tex]\large\boxed{y\leq8\to\{y\ |\ y\leq8\}\to y\in(-\infty,\ 8]}[/tex]
Step-by-step explanation:
[tex]-1+4y\leq31\qquad\text{add 1 to both sides}\\\\-1+1+4y\leq31+1\\\\4y\leq32\qquad\text{divide both sides by 4}\\\\\dfrac{4y}{4}\leq\dfrac{32}{4}\\\\y\leq8[/tex]
