triangular

Everyday

1. Triangular means shaped like a triangle, with three sides and three corners. tree →
2. A triangular number is a number of dots that can make a triangle: 1, 3, 6, 10, 15 … tree →

In the lessons

a shape with 3 sides: perimeter is the sum of the 3 sides; in maths: triangular prisms and pyramids, triangular numbers; in everyday life: triangular road signs (warnings), sandwiches cut into triangles, a triangular flag

Examples

• A triangular garden has sides 5, 6 and 7 m. tree →
• Find the perimeter of the triangular field. tree →
• A triangular flag. tree →
• How many corners has a triangular piece? tree →
• Warning road signs are triangular. tree →
• She cut the sandwiches into triangular halves. tree →
• A triangular prism has 2 triangular faces. tree →
• 1, 3, 6 and 10 are triangular numbers. tree →
• He had two triangular pieces of tile in his head, instead of eyes; his mouth was made of an old broken rake, and was, of course, furnished with teeth. tree →

Note

Hidden fact: a triangle has 3 sides and 3 corners. Perimeter = sum of the three sides. Triangular numbers grow by 2, 3, 4 … each time. A triangular prism has 5 faces, 9 edges and 6 vertices.

In Jewish tradition

a shape with 3 sides: perimeter is the sum of the 3 sides; in maths: triangular prisms and pyramids, triangular numbers; in everyday life: triangular road signs (warnings), sandwiches cut into triangles, a triangular flag

Examples

• arranged in a triangular form and the sphere of void encompassing them was symbolized by a circle. (Mordell, The Origin of Letters and Numerals according to Sefer Yetzirah (1914)) tree →

Note

Hidden fact: a triangle has 3 sides and 3 corners. Perimeter = sum of the three sides. Triangular numbers grow by 2, 3, 4 … each time. A triangular prism has 5 faces, 9 edges and 6 vertices.