The perimeter of a square is 32 cm what is the length of a diagonal

First you should draw yourself a square. Since you know it is a square you can find each side by dividing it by 4. 32/4 = 8. Since it is a square you know that both the length and width are 8. If you draw in the diagonal that is a right triangle. Use the Pythagorean theorem a^2 + b^2 = c^2 to find the length of the diagonal.

8^2 + 8^2 = c^2