Câu 3: Trang 55 - sách giáo khoa (SGK) Toán tiếng anh lớp 4:Draw a square ABCD with sides 5 cm,...

In summary, after drawing the square ABCD with sides of 5 cm, we find that the diagonals AC and BD are perpendicular to each other and equal in length.

To check if the diagonals AC and BD are equal, we can measure the lengths of the diagonals using a ruler. If the lengths are the same, then the diagonals are equal.

To check if the diagonals AC and BD are perpendicular to each other, we can measure the angles formed by the diagonals at their point of intersection. If the angles are 90 degrees, then the diagonals are perpendicular.

To draw a square ABCD with sides 5 cm, we first draw a straight line of 5 cm and then draw another line perpendicular to the first line of the same length to form the square.