Jack is looking at the eagle on top of a building. the height of the building is 60 ft. approximately how many feet is jack from the base of the building?

The angle of depression from the top of the building is missing, therefore, we will consider it to be 60°, for your understanding.

Now, 
According to the right triangle rule, we are given the angle, the adjacent side, and we have to find the opposite side.

Therefore,
Using SOH CAH TOA laws,

SOH means,
Sine Ф = Opposite / Hypotenuse

CAH means,
Cosine Ф = Adjacent / Hypotenuse

TOA means,
Tangent Ф = Opposite / Adjacent

Where,
Ф is the angle of depression.

Hence, 
Using Tangent Ф   = Opposite / Adjacent         
          Tangent 60° = Opposite / 60
                        1.73 = Opposite / 60
                1.73 × 60 = Opposite
               Opposite = 103.8 feet away from the base of the building