Question

If two lines, L1 and L2, which lie in the same plane, are both perpendicular to a third line L3, in the same plane as the first two, what do we know about L1 and L2?

Answer 1

They should either coincide or be parallel.

Explanation:

Let's Assume that Lines `L_1, L_2` and `L_3` lie in the same plane `P`.

As per the question, `L_1` perpendicular `L_3` and `L_2` perpendicular `L_3`.

As they are in the same plane, They will form equal corresponding angles respect to the Line `L_3`. [Both are `90^@`].

In that case, they will be parallel.

If, the lines are perpendicular on the same point, they will coincide.

Hope this helps.