Question

what is cos a?
a 7/13
b 5/13
c 12/13
d 12/5

Explanation:

Step1: Recall the cosine formula

In a right - triangle, \(\cos\theta=\frac{\text{adjacent side}}{\text{hypotenuse}}\). For angle \(A\), the adjacent side to angle \(A\) is \(AB = 12\), and the hypotenuse is \(AC=13\).

Step2: Calculate \(\cos A\)

Using the formula \(\cos A=\frac{AB}{AC}\), substituting \(AB = 12\) and \(AC = 13\), we get \(\cos A=\frac{12}{13}\).

Answer:

\(\frac{12}{13}\) (Option C)