Question 614320
The perimeter of a square is 4*S where S = x+5.
The perimeter of an equilateral triangle is 3*s where s = 3x.
The perimeters are equal, so...
4(x+5) = 3(3x) Simplify.
4x+20 = 9x Subtract 4x from both sides.
20 = 5x Divide both sides by 5.
x = 4
x+ 5 = 9
3x = 12.
The sides of the equilateral triangle are 12 each.