### Теория:

A rectangle is a quadrilateral with four right angles. In a rectangle, all the angles are equal $$(360°/4 = 90°)$$. Furthermore, the opposite sides are parallel and equal, and diagonals bisect each other.

Properties of rectangles:
• Opposite sides of a rectangle are equal and parallel.
• All the angles of a rectangle are $$90°$$.
• Diagonals of a rectangle bisect each other.
First Property of a rectangle: Opposite sides of a rectangle are equal and parallel.

$$AB = DC$$ & $$BC = DA$$
Hence, Opposite side are equal and parallel
The Second property of the rectangle: All the angles of a rectangle are $$90°$$.

Let us consider a rectangle $$ABCD$$.
$$∠A = ∠B = ∠C = ∠D$$
Hence, each angle of a rectangle measures $$90°$$.
The third property of rectangle: Diagonals of a rectangle bisect each other.

In rectangle $$ABCD$$, diagonals bisect the angles.
$$OA = OC$$ and $$OB = OD$$
Thus the diagonals bisect each other in a rectangle.