Answer:
![75.52^\circ](https://img.qammunity.org/2021/formulas/mathematics/high-school/98k129t0w19rxgtc2g1b0u9uld4ka5s620.png)
Explanation:
Given that:
The length of the ladder = 30 ft
Distance between bottom of ladder and wall =
of its length
To find:
Angle made between the ladder and ground = ?
Solution:
This situation can be compared with a right angled
as shown in the attached image in the answer area.
Side AC being the hypotenuse has the ladder along it.
AB is the wall.
BC is the distance between the wall and foot of ladder.
Formula for cosine trigonometric ratio:
![cos\theta = (Base)/(Hypotenuse)](https://img.qammunity.org/2021/formulas/mathematics/college/35rf0ri6bno4s20tps8d0wqij39ba2u7ia.png)
In
:
![cosC=(BC)/(AC)](https://img.qammunity.org/2021/formulas/mathematics/high-school/tck1r7sw57250jtf6q1dcrfmj9mug057a3.png)
Putting the values:
![BC=(AC)/(4)](https://img.qammunity.org/2021/formulas/mathematics/high-school/c3mi567ymkqmqnhlib7ofs6wwevjxb1xmo.png)
![cosC=\frac{\frac{AC}4}{AC}\\\Rightarrow cos C = (1)/(4)\\\Rightarrow \angle C = cos^(-1)(0.25)\\\Rightarrow \angle C =\bold{75.52^\circ}](https://img.qammunity.org/2021/formulas/mathematics/high-school/h1vsk6hfy2jgxjy5jz7d6yrdvr9es0aqmf.png)