Answer: 1600
Explanation: If angles E and D are the same with the lines intersecting at B, then that means that A and C are also the same, as the opposite angles formed at point B are also the same, so you have two similar triangles.
Similar triangles have proportional lengths. So we know length CD is 800 ft and its similar leg on the other side (AE) is unknown.
So we need to find two known lengths, one on the large and one on the small, that are similar.
BE is 1400 ft and BD is 700 ft. Those are you two known similar legs. So now we can use them in a proportion to find AE.
We will do the line ending at B over the line that doesn't include B.
Large triangle:
x
1400
Small triangle:
800
700
Set them up in a proportion:
x
1400
=
800
700
Solve for x:
⇒7x=11200
⇒x=1600 ft
Sorry if I get it wrong I tried my hardest
