brainliest . anything . follow you but please help me this question

Answer: Not a right triangle
Step-by-step explanation:
We know that the perimeter is 18 cm, and the sides are 7, 3, and x
[tex]18 - 7 - 3 = 8[/tex]
[tex]3^{2} + 7^{2} \neq 8^{2}[/tex]
Therefore, it is not a right triangle.
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