What is the answer I don't know how to solve this!
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[tex]a = 9[/tex]
[tex]b = 12[/tex]
[tex]c = \sqrt{ {a}^{2} + {b}^{2} } = \sqrt{ {9}^{2} + {12}^{2} } = \sqrt{81 + 144} = \sqrt{225} = 15[/tex]
[tex]p = a + b + c = 9 + 12 + 15 = 36[/tex]
Answer: 36.