Test on 4/14. Geometry. Picture included Please help ASAP please

http://img.photobucket.com/albums/v2...e/441fd7bf.gif

The ones I know are know are correct but no well understood:

a) 1:1 because both triangles have the same base? So 16:16 = 1:1 right?

b) same method as ^

d) 9:16 because using the similar triangles area ratio formula. The method of similar trianges i used was AA because of the parallel lines right?

The ones I don't understand at all but I know the answers. I'm all confused:

c) The answer is 1:1. I think you can assume that the height of both triangles are the same? How can it be 1:1 if there are no other measurements of the triangles?

e) The answer is 3:4. I figured maybe you do simplfy 12/16 to get 3:4 but I have no clue why because the the triangles that the question is asking for doesn't have 12 or 16?

Im so confused. please help ASAP. Thanks... :cry: