Based on the Pythagorean Theorem, if triangle \( MNO \) is a right triangle, the relationship of the sides can be expressed as:
\[ a^2 = m^2 + n^2 \]
Here, \( a \) represents the length of the hypotenuse (the side opposite the right angle), and \( m \) and \( n \) represent the lengths of the other two sides.
If you have specific values for the sides \( m \) and \( n \), you can substitute them into the equation \( a^2 = m^2 + n^2 \) to find the length of the hypotenuse \( a \). If triangle \( MNO \) is not a right triangle, then the Pythagorean Theorem does not apply in this straightforward manner.