Answer :
The length of side of the rectangle is 6 mm
Since the rectangle has an area of A = 36 mm² and the rectangle has all its sides the same length, then, it is a square. We know that the area of a square A = L² where L = length of sides of square.
Length of side of rectangle
Since we require the length of sides of the rectangle, we make L subject of the formula.
So, L = √A
Now, since the area of the rectangle, A = 36 mm², substituting the value of the variable into the equation, we have
L = √A
L = √(36 mm²)
L = 6 mm
The length of side of the rectangle is 6 mm
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