Identify the geometric shapes and the task to be performed.

Geometric Shapes and Task

The image displays two triangles, ╨ABO and ╨CDO, which intersect at point O. Several geometric properties are indicated:

• Angle ∠A is a right angle (indicated by a square symbol).
• Angle ∠C is a right angle (indicated by a square symbol).
• Segment AO is marked with a single tick, implying it is equal to some other segment. However, there is no other segment marked with a single tick.
• Segment BO is marked with a double tick, implying it is equal to some other segment. However, there is no other segment marked with a double tick.
• Segment CO is marked with a single tick. Based on the markings, it is implied that AO = CO.
• Segment DO is marked with a double tick. Based on the markings, it is implied that BO = DO.

The task is to prove that triangle ABO is congruent to triangle CDO (╨ ABO = ╨ CDO).