Solution:
Given that,
A 45 foot ladder is leaning against a building
The foot of the ladder is positioned 10 feet from the base of the building
The figure is attached below
Let,
AB = foot of the ladder from the base of the building
AB = 10 feet
AC = length of ladder
AC = 45 feet
Then by definition of cos,
[tex]cos\ \theta = \frac{AB}{AC} \\\\cos\ \theta = \frac{10}{45}\\\\\theta = cos^{-1} 0.222 \\\\\theta = 77.17[/tex]
Thus, the angle at which the ladder meets the ground is 77.17 degree
