Täisnurkne

Täisnurkne is an Estonian word that translates to "right-angled" or "rectangular" in English. It is primarily used in geometry to describe shapes and angles. A täisnurk is a right angle, which measures exactly 90 degrees.

A täisnurkne kolmnurk is a right-angled triangle, a triangle that contains one right angle. The sides adjacent to the right angle are called cathetus (kateet), and the side opposite the right angle is called the hypotenuse (hüpotenuus).

A täisnurkne nelinurk is a rectangle, a quadrilateral with four right angles. Opposite sides of a rectangle are equal in length and parallel. A square is a special type of rectangle where all four sides are equal in length.

The concept of täisnurkne is fundamental in Euclidean geometry and has applications in various fields, including architecture, engineering, and design, where precise angles and shapes are crucial. It is a common term encountered in mathematics education in Estonia.