Question 262375
{{{drawing(400,181.82,-4,7,-2,3,

line(-3,0,5,0), line(-.5,-1,1,2), line(5,0,6,2),
line(-3.5,-1,-.5,-1),line(-3.5,-1,-3,0),line(1,2,6,2), 
locate(-3.5,-1,G), locate(-.5,-1,H), locate(-3,.5,N),
locate(-.3,.5,J),locate(5,0,K), locate(6,2.4,L), locate(1,2.4,M)

)}}}
<pre><font size = 4 color = "indigo"><b>
Here is an outline of the proof. You can use it to
write a two line proof.

Angles G and HJN are congruent because opposite internal
angles of parallelogram GHJN are congruent.

Angles HJN and KJM are vertical angles because H and M are collinear
and N and K are collinear

Angle HJN is congruent to angle KJM because
they are vertical angles.

Angles KJM and L are congruent because opposite internal
angles of parallelogram JKLM are congruent.

Angle G and anhle L are copngruent because they
are congruent to congruent vertical angles HJN and KJM

Edwin</pre>