In the figure below, what is the length of ad? i keep getting h, but it is not correct !

Find the inside angle B of the smaller triangle using the base (4) and height (6)
smaller part of B =  arctan(4/6) = 33.69 degrees
 full B = 90 degrees - smaller B gives you the other part of B for the left hand side

so 90 - 33.69 = 56.31

now AD =  6 x tan(56.31) = 9 feet
 answer is G

hope it helped have a good day mate