Let's check every point for the function:
---------------------
(3,15)
This point is on the line
------------------------
(3,6)
This point is not on the line
------------------------------
(-1,-5)
This point is on the line
----------------------
(0,1)
This point is not on the line
------------------------------
(4,2)
This point is not on the line
-----------------------------------
(-1,5)
This point is not on the line