A wire is first bent into the shape of a triangle. each side of the triangle is 20cm long. then the wire is bent and shaped into a square. what is the length of a side of the square

Length of Side of triangle=20cm

so, Length of wire = 3*20cm = 60cm [reason:triangle has 3 sides]

Then, Perimeter of square=Length of wire

or, 4l = 60

or, l = 60/4

or, l = 15

therefore, the length if side of the square is 15cm.