Question 251188
Draw two horizontal parallel lines and a non-perpendicular transversal cross from bottom left to top right. Label the top four angles 1, 2, 3, 4 from top left clockwise. Label the bottom four angles 5, 6, 7, 8 starting below the 4 also clockwise.

here are the pairs that are non-adjacent supplementaries:

1,6 ; 1,8 ; 2,5 ; 2,7 ; 3,6 ; 3,8 ; 4,5 ; 4,7.

A total of 8.