Please help me real quick with Geometry problem

Question

If two segments intersect, then they are not parallel. If two segments are not parallel, then they could be perpendicular. EF MN and intersect.

Answer 1

So long as the slopes are not the same then the

lines are not parallel and will intersect at some

point.  They are only perpendicular if they have

slopes that are negative reciprocals of each other.

 

EF ⊥MN IF m_EF = -1/m_MN

Answer 2

EF and MN could be perpendicular (yet not necessarily!).