Answer: The perimeter of a shape is the sum of all its sides.
From the diagram, we can see that the shaded shape is composed of a square and a rhombus.
The square has 4 sides of equal length, which is the same as the length of one of the diagonals of the rhombus.
The rhombus has 4 sides with two sides of equal length (the diagonals) and two sides of equal length (the parallel sides).
We can call the length of the diagonals of the rhombus as "d" and the length of the parallel sides of the rhombus as "s".
So, the perimeter of the shaded shape is:
Perimeter = 4s + 4d
It is not possible to find the perimeter with out knowing the length of the sides of the rhombus and the square.
Explanation: