Yes, all triangle angles add up to 180 degrees. This is a fundamental property of Euclidean geometry, which governs the relationships between angles and sides in flat, two-dimensional spaces.
To understand why this is true, imagine a triangle on a plane. The three angles inside the triangle are created by the intersection of the triangle’s sides. If you were to extend one of the sides outwards and draw a line parallel to the opposite side through the vertex where the angle is formed, you would see that the angle on the outside and the adjacent angles inside the triangle are complementary, meaning they add up to 180 degrees.
This relationship holds true for all types of triangles, whether they are scalene, isosceles, or equilateral. However, it’s important to note that this rule applies only to triangles in a flat plane. In non-Euclidean geometries, such as on the surface of a sphere, the sum of angles in a triangle can be greater than 180 degrees. Nevertheless, for all practical purposes in standard geometry, we can confidently say that the angles in a triangle will always sum to 180 degrees.