How to measure the area of a plot of land ABCDE consisting of the following 3 triangles(without using Heron's formula for the measure of areas of triangles where all sides are known):

[top triangle 1 ]BCD -side BC = 124 m

- side CD = 47 m

- side BD = unknown length [side BD is the top side of middle triangle 2 aswell]

[middle triangle 2]ABD - side BD = unknown length

- side AD = 82 m [side DA is the top side of lower triangle 3 aswell]

- side AB = 54 m

- angle BAD is a right angle

[lower triangle 3]ADE - side AD = 82m

- side DE = 28 m

- side AE = 96 m

Below is a useful visual representation of the situation.I've been stuck on this question for quite a while and would appreciate it a lot if someone could help me out with this one.