find perimeter and area of each triangle round to nearest hundredth

Given is a right angled triangle. Consider the figure,
Using the trignoetric funcyion tan, we have,
[tex]\begin{gathered} \tan 18=\frac{a}{12} \\ a=12\times\tan 18=3.89 \end{gathered}[/tex]Now, as we have base, a = 3.89 and height c = 12, the perimeter can be calcualted as,
[tex]\begin{gathered} P=a+c+\sqrt[]{a^2+c^2} \\ \text{ =3.89+12+}\sqrt[]{3.89^2+12^2}=28.5=29 \end{gathered}[/tex]Now, the area can be calculated as,
[tex]\begin{gathered} A=\frac{1}{2}ac \\ \text{ =1/2}\times3.89\times12=23.34=23 \end{gathered}[/tex]