What is the length of AC Quadrilateral AB CD is a square BC?

In a square, all sides are equal. If quadrilateral ABCD is a square and BC is one of its sides, then the length of side AC (the diagonal) can be calculated using the Pythagorean theorem. For a square with side length ( s ), the length of the diagonal ( AC ) is given by ( AC = s\sqrt{2} ). Therefore, if you know the length of side BC, you can use that to find the length of AC.