[tex]x^{2} + (4\sqrt{3})^{2} = 9^{2} \\x^{2} + 16*3=81\\x^{2} + 48=81\\x^{2} = 81-48\\x^{2} = 33\\x=\sqrt{33} \\\\P= \frac{4\sqrt{3}*\sqrt{33} }{2} \\\P= 2\sqrt{99} \\P=2*3\sqrt{11} \\\P= 6\sqrt{11} \\\L= {\sqrt{33} + 4\sqrt{3} + 9 \\\\[/tex]
