Perímetro é a soma dos lados.
[tex]P=\sqrt{18}+\sqrt{50} +\sqrt{98}\\\\P=\sqrt{9\cdot2}+\sqrt{25\cdot2} +\sqrt{49\cdot2}\\\\P=\sqrt{9}\cdot\sqrt{2}+\sqrt{25}\cdot\sqrt{2} +\sqrt{49}\cdot\sqrt{2}\\\\P=3\sqrt{2}+5\sqrt{2}+7\sqrt{2}\\\\P=15\sqrt{2}\\[/tex]
