[tex]a + b + b + c + c + a = \sqrt{2} + \sqrt{18} + \sqrt{72} [/tex]
[tex]2a + 2b + 2c = \sqrt{2} + 3 \sqrt{2} + 6 \sqrt{2} [/tex]
[tex]2 \times (a + b + c) = 10 \sqrt{2} [/tex]
[tex]a + b + c = 5 \sqrt{2} [/tex]
[tex]a + b + c - a + b = 5\sqrt{2} - \sqrt{2} [/tex]
[tex]c = 4 \sqrt{2} [/tex]
[tex]b + 4 \sqrt{2} = 3 \sqrt{2} [/tex]
[tex]b = - \sqrt{2} [/tex]
[tex]4 \sqrt{2} + a = 6 \sqrt{2} [/tex]
[tex]a = 2 \sqrt{2} [/tex]