Answer:
The length of a side of the square is given by x
The length of a side of the equilateral triangle is given by x=1
Given is : The perimeter of a square is equal to the perimeter of an equilateral triangle.
Perimeter of square is given as 4 x side.
Perimeter of equilateral triangle is given as 3 x side.
So, we will make both equal.

As x = 1 for triangle, the equation becomes:

So,
