The Tangent Ratio

The next problem involves finding the height of a tree. Use your notes to solve the next series of exercises.

To measure the height of a tree, Alma walked 125 ft from the tree and measured a [tex]$32^{\circ}$[/tex] angle from the ground to the top of the tree. Estimate the height of the tree to the nearest foot.

Which tangent ratio do you use to find the height?

A. [tex]$h=\frac{\tan 32}{125}$[/tex]
B. [tex]$\tan 32^{\circ}=\frac{h}{125}$[/tex]
C. [tex]$\tan 32^{\circ}=\frac{125}{h}$[/tex]
D. [tex]$h=\frac{125}{\tan 32}$[/tex]



Answer :

To solve this problem, we need to understand how to use the tangent ratio. The tangent ratio in trigonometry relates the angle of a right triangle to the lengths of the opposite side and the adjacent side. The tangent of an angle [tex]\( \theta \)[/tex] is defined as:

[tex]\[ \tan(\theta) = \frac{\text{opposite}}{\text{adjacent}} \][/tex]

In this problem:

- The angle [tex]\( \theta \)[/tex] is [tex]\(32^{\circ}\)[/tex].
- The adjacent side to this angle is the distance Alma walked from the tree, which is 125 feet.
- The opposite side is the height of the tree, which we need to find.

Given [tex]\(\theta = 32^{\circ}\)[/tex], let's denote the height of the tree as [tex]\(h\)[/tex]. Applying the tangent ratio, we have:

[tex]\[ \tan(32^{\circ}) = \frac{h}{125} \][/tex]

From this equation, we can solve for [tex]\(h\)[/tex] by multiplying both sides by 125:

[tex]\[ h = 125 \cdot \tan(32^{\circ}) \][/tex]

Among the given options, Option B:

[tex]\[ \tan 32^{\circ}=\frac{h}{125} \][/tex]

is the correct choice as it correctly sets up the tangent ratio for solving for the height [tex]\(h\)[/tex] of the tree.

Therefore, the correct tangent ratio to use for finding the height of the tree is:

[tex]\[ \tan 32^{\circ}=\frac{h}{125} \][/tex]

And the height of the tree is approximately 78 feet when rounded to the nearest foot.