51. Find the length of the unknown side x of this triangle, evaluate your answer to two decimal places.

x = 13.02 units

Step-by-step explanation:

The radius of this circle is 10 and so the diameter is 20.  The measure of the angle opposite side x is found as follows:

                      adj side

 cos theta = = 18/20.  Find theta:

                      hypotenuse

theta = arccos 18/20 = 0.451 radian.

Now use the sine function to find x:

                                          x                       x

sin 0.451 radian      = = = 0.651

                                    hypotenuse          20

which results in x = 20(0.651) = 13.02

x = 13.02 units

answer: the dogs need to shift their focus to human scent.

its because the dogs being trained are for search and rescue thus they need to be able to track humans and their specific scent