Answer:
The angle of depression from Platform A to Platform B is 
Step-by-step explanation:
Refer the attached figure
The horizontal distance between the platforms is 500 feet i.e. BC = 500
The length of the zip-line is 685 feet i.e. AB = 685
We are supposed to find the angle of depression from Platform A to Platform B
Hypotenuse = 685
Base = 500

Hence the angle of depression from Platform A to Platform B is 
3/10 or 30/100 are left handed boys bc that is 30% converted into a fraction
If;
A = Adjacent
O = Opposite
H = Hypotenuse
Then,
Sin Ф = O/H
Cos Ф = A/H
Therefore,
(Sin Ф)/Cos Ф) = (O/H)/(A/H) = (O/H)*(H/A) = O/A
Now,
tan Ф = O/A ----
Therefore, it is true that
tan Ф = SinФ/CosФ
Just around the 15 and 3. So it would be
(15-3)x4+9=57
This is because (15-3)= 12
12x4=48
48+9= 57
Udjejejjejejejejejwkdjrjdkjdhfkndbdbf
Lol just trying to be weird