Respuesta :

Answer:

Step-by-step explanation:

Part b:  Find the length of the sidewalk.  The walk is the hypotenuse of a right 30-60-90 triangle with horizontal side 2√3.  Using the 30° angle as the reference angle, we get the following from the definition of the cosine function:

                                     

cos 30° = adj / hyp, or:

                           

  √3       2√3

 ------- = --------

     2        hyp

This simplifies to

     1          2

 -------- = -------

      2        hyp

Cross multiplying results in:  hyp = 4.  The sidewalk length is 4 miles.

a.  The width of the park can be found using the sine function, the now-known hypotenuse and the 30° angle:

                               1       opposite side

sin 30 degrees = ----- = -------------------------   or 2(opp side) = 4.

                               2                 4

Then the opp side, which is the width of the park, is 2.