Given:
In triangle ABC, [tex]m\angle A=66^\circ, AB=5\text{ mi}[/tex].
To find:
The angle of depression from point A to point C.
Solution:
According to angle sum property, the sum of all interior angles of a triangle is 180 degrees.
In triangle ABC,
[tex]m\angle A+m\angle B+m\angle C=180^\circ[/tex]
[tex]66^\circ+90^\circ+m\angle C=180^\circ[/tex]
[tex]156^\circ+m\angle C=180^\circ[/tex]
[tex]m\angle C=180^\circ-156^\circ[/tex]
[tex]m\angle C=24^\circ[/tex]
We know that if a transversal line intersect the two parallel lines, then alternate interior angles are equal. So, the angle of depression from point A to point C is equal to the measure of angle C in triangle ABC.
Therefore, the angle of depression is 24 degrees.
