From the diagram below, if AB = 12, BC = 5, and AC = 13, find the tangent of < A.

Let's rotate the triangle with respect to ∠A as the focused angle and add the given details:
Recall the standard formula of a Tangent Function:
[tex]\text{ Tangent \lparen}\theta)\text{ = }\frac{\text{ Opposite Side}}{\text{ Adjacent Side}}[/tex]Thus, with respect to the problem, Tangent A is:
[tex]\text{ Tangent \lparen A\rparen = }\frac{\text{ 5 }}{\text{12}}[/tex]Therefore, the answer is CHOICE C : 5/12