Let's check every point for the function:
[tex]y=5x[/tex]---------------------
(3,15)
[tex]\begin{gathered} 15=5(3)=15 \\ 15=15 \\ True \end{gathered}[/tex]This point is on the line
------------------------
(3,6)
[tex]\begin{gathered} 6=5(3)=15 \\ 6=15 \\ False \end{gathered}[/tex]This point is not on the line
------------------------------
(-1,-5)
[tex]\begin{gathered} -5=5(-1)=-5 \\ -5=-5 \\ True \end{gathered}[/tex]This point is on the line
----------------------
(0,1)
[tex]\begin{gathered} 1=5(0)=0 \\ 1=0 \\ False \end{gathered}[/tex]This point is not on the line
------------------------------
(4,2)
[tex]\begin{gathered} 2=5(4)=20 \\ 2=20 \\ False \end{gathered}[/tex]This point is not on the line
-----------------------------------
(-1,5)
[tex]\begin{gathered} 5=5(-1)=-5 \\ 5=-5 \\ False \end{gathered}[/tex]This point is not on the line