The perimeter should be equals to 37 since 16 + 16 + 5 = 37
The other side cannot be equals to 5 since the sum of two sides is not greater than the remaining side, no triangle can be made ( 5 + 5 is not greater than 16)
So the remaining possibility is 16 + 16 + 5 = 37
I hope you understand and this helps.
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