In trapezoid ABCD with bases BC and AD, diagonals AC and BD meet at point O. Prove that the areas of triangles AOB and COD are equal.
Consider triangles ABC and BCD. You can see that their heights, CH and AH1 are the same. Since these triangles have a common base, these triangles are of equal size. If you separate the triangle BOC from them, you will also get triangles AOB and COD of the same area, etc.
One of the components of a person's success in our time is receiving modern high-quality education, mastering the knowledge, skills and abilities necessary for life in society. A person today needs to study almost all his life, mastering everything new and new, acquiring the necessary professional qualities.