Similar triangles are two triangles that have the same shape but are not necessarily the same size. This means that their corresponding angles are equal, and their corresponding sides are in proportion to each other. When two triangles are similar, their corresponding sides are in the same ratio, known as the scale factor. This concept is important in geometry and trigonometry as it allows us to solve for unknown sides or angles in triangles by using the properties of similar triangles. **

The symbol with the 3 triangles is called the 'Triquetra' or 'Trinity Knot'. It is a Celtic symbol representing the concept of the trinity, such as mind, body, and spirit or past, present, and future. It is often associated with the Christian Holy Trinity as well, symbolizing the Father, Son, and Holy Spirit. The symbol is also sometimes used to represent the interconnectedness of the three realms of earth, sea, and sky in Celtic mythology. **

Similarity of triangles refers to the property where two triangles have the same shape but possibly different sizes. This means that the corresponding angles of the triangles are equal, and the corresponding sides are in proportion to each other. When two triangles are similar, their corresponding sides are in the same ratio, known as the scale factor. This concept is important in geometry as it helps in solving problems involving proportions and finding unknown side lengths or angles in similar triangles. **

The modern concept of atoms is based on the idea that they are the fundamental building blocks of matter. Atoms are composed of a nucleus containing protons and neutrons, surrounded by electrons in orbitals. They are incredibly small and make up everything in the universe, from the air we breathe to the stars in the sky. The study of atoms and their interactions is crucial in understanding the physical and chemical properties of substances. **

The concept of the similarity of triangles in mathematics refers to the relationship between two triangles that have the same shape but different sizes. When two triangles are similar, their corresponding angles are equal and their corresponding sides are in proportion to each other. This means that if you were to enlarge or shrink one of the triangles, it would still maintain the same shape as the other triangle. The concept of similarity of triangles is important in various mathematical and geometric applications, such as solving for unknown side lengths and angles in similar triangles. **

The translation of "lumina nova" in lesson 1 at school is "new light" in English. This phrase is likely used to introduce the concept of new knowledge or understanding, symbolizing the illumination of new ideas or perspectives. It is a fitting phrase to start off a lesson, as it signifies the beginning of a new learning experience. **

Slope triangles are a visual representation of the slope of a line on a graph. They are formed by drawing a right-angled triangle on the graph, with one side parallel to the x-axis and the other parallel to the y-axis. The slope of the line is then calculated by comparing the vertical and horizontal lengths of the triangle. Slope triangles are a helpful tool for understanding and visualizing the concept of slope in mathematics. **

Rice triangles, also known as onigiri, are a popular Japanese snack made of rice formed into a triangular or cylindrical shape and often wrapped in seaweed. They are typically filled with ingredients such as pickled plum, salmon, or tuna. Rice triangles are a convenient and portable snack commonly found in Japanese convenience stores and are enjoyed for their delicious flavor and satisfying texture. **