Two sides of a four sided figure have negative slopes which are the endpoints of the sides of this figure
(-4,-4) (-4,-1) (-1, -4) (-1,-1)
-2,-4 (-1 -1), (1,-1) , (2 -4)
1,1 (2,4) (5, 4)( 4,1)
(1,4), (2,1) (5,1) (4,4)
(-4,-4) (-4,-1) (-1, -4) (-1,-1)
-2,-4 (-1 -1), (1,-1) , (2 -4)
1,1 (2,4) (5, 4)( 4,1)
(1,4), (2,1) (5,1) (4,4)