Answer:
An equilateral triangle has all 3 sides the same length
If one side of the triangle has length x, the perimeter = 3x
If one side of the square is 5 less than a side of the triangle
then the square has side length x-5 and perimeter 4(x-5) = 4x-20
Since the perimeter of the triangle is 7 more than
the perimeter of the square then our equation is:
3x = 4x-20+7
3x = 4x-13
x = 13
The sides of the triangle are 13 inches
The sides of the square are 13-5=8 inches
