The perimeter of the equilateral triangle is 3s and s=4x so the perimeter is:
12x
And we are told that the perimeter of the square is the same. And that perimeter is 4s where s=(x+6) so that perimeter is equal to
4x+24, and again, we are told that these two values are equal so we can solve for x...
12x=4x+24
8x=24
x=3 and if x=3 then the side length is (x+6)=9
So the area of the square is always A=s^2 and s=9 thus:
A=9^2
A=81 u^2
