Use a rectangle 4 cm long and 3 cm wide to make a square as shown in the figure below. What is the minimum side length of the square? (you can draw a picture in the picture first, then calculate)

Use a rectangle 4 cm long and 3 cm wide to make a square as shown in the figure below. What is the minimum side length of the square? (you can draw a picture in the picture first, then calculate)

4 × 3 = 12, that is, the side length of the square is 12 cm