Given:-
A triangle with side length 3 and 12.
To find the value of angle A.
So the formula used is,
[tex]CosA=\frac{Adjacent\text{ side}}{Hypotneus}[/tex]
Substituting the values. we get,
[tex]\begin{gathered} CosA=\frac{3}{12} \\ A=cos^{-1}(\frac{1}{4}) \\ A=75.52 \end{gathered}[/tex]
So the value of A is 75.52 degree.
