Question

If Y co-ordinate of a point is zero then this point always lies​

Answer 1

on the x-axis

Explanation:

(assuming the point is on a rectangular coordinate plane) The y-coordinate determines where a point is "vertically". The x-axis is equal to y=0, so if the y-coordinate of a point is 0, i.e. (x,0), the point always lies on the x-axis.