Respuesta :

If this is a right triangle, then it would have to be a^2 + b^2 = c^2

assuming that the lengths are not the hypotenuse, then we can square the two numbers.

81 + 256 = c^2
337 = c^2
√337 = c

to go into decimals, the answer would be:    c = 18.358
The answer is:  " 25 cm " .
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This would refer to a right triangle;

 a² + b² = c² ;

In which :  3² + 4² = 5² ;

or:  9 + 16 = 25 .
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