What is the sum of the angles in a triangle?

The sum of the angles in a triangle is always 180 degrees. This is a fundamental property of triangles in Euclidean geometry, which states that no matter the type or shape of the triangle—whether it is an equilateral, isosceles, or scalene triangle—the internal angles will always add up to exactly 180 degrees.

This property can be demonstrated using various methods, such as by drawing a triangle and extending one of its sides. By doing so, one can create adjacent angles that clearly show how the internal angles relate to a straight line, reinforcing that their total must equal 180 degrees.

Understanding this principle is crucial not only for solving basic geometry problems but also for more complex applications involving triangles, such as the calculation of missing angles or the use of trigonometric ratios in various fields.