Each of the four shaded rectangles has an area of 21 cm square and a perimeter of 20cm what is the perimeter of the square formed in middle

16cm

Step-by-step explanation:

Given

--- rectangles

Required

The perimeter of square in the middle

The area of a rectangle is:

So, we have:

The perimeter is:

So, we have:

Divide by 2

Make L the subject

Substitute in

Open bracket

Rewrite as:

Expand

Factorize

Factor out W - 3

Solve for 7

We have:

This means that:

The length (l) of the square is:

---- the difference between the dimension of the rectangle

The perimeter is:

we don't have enough info to solve this