Answer:
A=674.5cm square
Step-by-step explanation:
First, using pythagoras theorem:
Cos x =2/5-90=66.4
This is angle ACD.
Then 1/2 absinC=1/2(5x4)sin66.4
=664.2cm square
Next, find angle DCB by 90-23.578=66.4
And angle CBD by 180-30-66.4=23.578
Use sin23.578=4.58/H
H=11.45cm(length of d)
Now, use 1/2absinC again to find the area of another part of the triangle.
1/2 11.45x4.5sin23.6=10.31cm square
Lastly add them up!
A=664.2-10.31cm =674.5cm square.
