Respuesta :

bayosanuade

Answer: 7cm

Step-by-step explanation:

The perimeter of a triangle is calculated by adding the length of the 3 sides together. Let the third side be x , then

x + 9 + 6 = 22

x + 15 = 22

Subtract 15 from both sides , that is

x = 22 - 15

x = 7

Therefore : the third side is 7cm

Larrysammz

Answer:

Step-by-step explanation:

perimeter of a triangle is the addition of all sides

22 - ( 9+6)

22 - 15

7