Answer:
Yea that problem is a bit confusing,
2y should be double of what y is, which is 4x+5
Then 2y says 8x+15, when it should be 8x+10.
I feel bad cause I am sure the teacher is wrong on this, he/she had probably made a typo, or you made a typo, but that's ok! We all make typos!
The teacher would be extra rude if they marked you wrong on this, cause the question itself is not written "properly"
For AD to be parallel 2x+4º should be equal to 79º
2(37)+4 = 78º
78º<79º
Since they aren't equal the lines are not parallel to each other.