I was using Desmos to try to find the medians of a triangle given its vertices using $A(x_1, y_1), B(x_2, y_2)$ and $C(x_3, y_3)$ as the coordinates. When I derived a direct formulae and plugged it in, I got the medians. However, along with these medians I also got certain equations of lines parallel to the $y$-axis through each vertex.
I think I accidentally found joint equations of the median line and a lines parallel to the y-axis through the vertices.
I have literally no idea why my median equations would be joint equations, and I really don't know how to eliminate the extra equations from my graph. Could someone help tell me if I've done something incorrect?
Edit: Another thing I've begun to notice is that the parallel lines vanish when the abscissa of the corresponding vertex is an integer, but reappear when its a non-integer value.