Art, Music, and Creative Writing homework help. 2. In a certain right triangle, the two sides that are perpendicular to each other are 5 m and 7 m long. What is the length of the third side? 3. A right triangle has a hypotenuse of length 3 m, and one of its angles is 30. What is the length of (a) the side opposite the 30 angle and (b) the side adjacent to the 30 angle?