First we must find area of a single square.
Meaning we divide total area of 80 centimetres squared by 5 since we have 5 squares in the shape.
Now from the picture we can see that the perimeter of shape is combined by 4 times 3 times the length of side of 1 square.
So we need to find side of 1 square.
As we stated before the formula for perimeter of this shape is:
The perimeter of shape is 48 centimetres.
Hope this helps.
r3t40