[tex] \frac{ {a}^{2} \sqrt{3} }{4} [/tex]
P1 =
[tex] \frac{3 \times 3}{2} = 4.5[/tex]
P2 =
[tex] \frac{(3 \sqrt{2})^{2} \times \sqrt{3} }{4} = \frac{18 \sqrt{3} }{4} = \frac{9 \sqrt{3} }{2} [/tex]
Pc =
[tex] \frac{9 \sqrt{3} }{2} + 3 \times 4.5 = \frac{9 \sqrt{3} }{2} + 13.5[/tex]