Question

Can someone please help me find the value of x?

Answer 1

The triangle shown in the exercise is a Right triangle, because it has an angle that measures 90 degrees (also called "Right angle").

By definition, the angle of depression is the angle formed by the horizontal line from the observer and the line of sight to an object that is below the horizontal.

Knowing the above, you know that:

`Angle\text{ }of\text{ }depression=x\degree`

Notice the following:

Therefore, you can use the following Inverse trigonometric function:

`\alpha=\cos ^(-1)((adjacent)/(hypotenuse))`

In this case:

`\begin{gathered} \alpha=x \\ adjacent=4 \\ hypotenuse=5 \end{gathered}`

Therefore, substituting values and evaluating, you get:

`\begin{gathered} x=\cos ^(-1)((4)/(5)) \\ \\ x\approx36.9\degree \end{gathered}`

The answer is: First option.