Answer: In problem 8, the lines are not parallel. In problem 10, the lines are parallel.
To determine if the lines are parallel. You need to check if the segments form on each side are proportion.
#8 check to see if: 2/1 = 3/1.2
If you cross multiply, you get 3 = 2.4 which is not true, so the lines are NOT parallel.
#10 check to see if: 6/5 = 9/7.5
If you cross multiply, you get 45 = 45 which is true, so the lines are parallel.