The system described in the question can be presented diagrammatically as shown below:
We can then bring out a diagram to solve as follows:
The angle θ is the required angle that we are to solve for.
We can use the Tangent Trigonometric Ratio to solve. The ratio is given to be
From the triangle,
Substituting these values, we have
We can then find the angle to be
The angle between the ladder and the wall is 27.8°.