Problem:
A ladder is leaning against a vertical wall makes an angle of 20⁰ with the ground. the foot of the ladder is 3 m from the wall. Find the height of the ladder.
Solution:
The situation of the problem can be diagrammed in the following right triangle:
where AC = 3m and BC = L.
Now, we want to find L. Thus, applying the appropriate trigonometric identity we have:
![cos(20^(\circ)\text{)}=(3m)/(L)](https://img.qammunity.org/2023/formulas/mathematics/college/v7072rk4cmybz4h8546nelimrrzg9xrxe4.png)
solving for L, we have:
![L\text{ = }(3)/(\cos (20))=\text{ 3.19}](https://img.qammunity.org/2023/formulas/mathematics/college/76gt8v4hus9mjf0l4pxeowqamwtqd3u76y.png)
thus, the correct answer is 3.19