A plane can’t be defined using less than two lines. Suppose there is only one line then, there can be infinitely many planes passing through it.

So, we atleast need two lines to uniquely define a plane.

Note: We can also have a line and a point not on it, 3 collinear points, two parallel lines or two intersecting lines. But all of these again form two or more lines only.

So, eventually we atleast need two lines to form a unique plane.

• This reply was modified 2 years, 2 months ago by ProtonsTalk.