Question

In a right - angled triangle, it is given that $A$ is an acute angle and $\tan A=\frac{5}{12}$ . Find the values of :

$\cos A$ $=\frac{12}{m}$, where m is,

Answer 1

$\tan A=\frac{5}{12}$

$\tan A=\frac{P}{B}=\frac{5}{12}$

$P=5,B=12$
Now, $H^2=P^2+B^2$

$H^2=5^2+{12}^2$

$H^2=169$

$H=13$
$\cos A=\frac{B}{H}=\frac{12}{13}$

$\therefore m=13$