You have to use the Pythagorean theorem but there is a little twist here since a square has has equal sides. So: x^2+x^2=8 2x^2=8 2/2x^2=8/2 x^2=4 √x^2=√4 x=2 The side of the square is 2. So now the area of a square is: Side×Side 2×2=4 The area of the square is 4 centimetres
