A |\ We have two right triangles in this problem. We are given that segment BC is 10', and that angle
| \ ACB is 35o
| \ So, we can use the tangent function (opposite/adjacent) to figure segment AB
| \ tan 35o = opp/10' = 0.700 x 10' = 7'
| \ We are given that segment BD = 5' (the height of the observer), which when added to segment AB
| \ gives us 12'
| \ Again, we can use the tangent function to calculate segment DE
B |_____\ C tan 35o = 12'/DE; 0.70 x DE = 12'/0.7; DE = 17.1'
| \ We can then use the Pythagorean theorem to solve for segment AE
| \ 12'2 + 17.1'2 = AE2; 144'2 + 294'2 = 438'2 = AE2; AE = 20.9'
D |_______\ E I am sorry that the spacing didn't work out as I hoped, but I think you will get the idea.