check the picture below.
now, we can simplify all those to
[tex]\bf cos(A)=\cfrac{24}{12\sqrt{5}}\implies \cfrac{2}{\sqrt{5}}\quad \stackrel{rationalizing~it}{\implies }\quad \cfrac{2\sqrt{5}}{5}
\\\\\\
sin(A)=\cfrac{12}{12\sqrt{5}}\implies \cfrac{1}{\sqrt{5}}\quad \stackrel{rationalizing~it}{\implies }\quad\cfrac{\sqrt{5}}{5}
\\\\\\
tan(A)=\cfrac{12}{24}\implies \cfrac{1}{2}[/tex]
