The six trigonometric ratios relate the sides of a right triangle to its angles.
For any right triangle the side opposite to the right angle is the hypotenuse.The side adjacent to the given angle is known as adjacent while the side opposite to the angle is known as the opposite.
In the given figure AC=17 is the hypotenuse.the side adjacent to <A is AB=8,the side opposite to <A is BC=15.
Tan of any angle is the ratio of opposite and adjacent.[tex]Tan A=\frac{Opposite}{adjacent}=\frac{15}{8}.[/tex]
Option A is the right answer.
