The angles in a triangle can only sum to which of the following?

In a triangle, the sum of the interior angles always equals 180 degrees. This is a fundamental property of triangles in Euclidean geometry. It can be demonstrated through various methods, such as using parallel lines and transversal angles or by dividing the triangle into two right triangles and calculating their angles.

This characteristic holds true regardless of the type of triangle, whether it is scalene, isosceles, or equilateral. Each triangle will consistently have angles that total 180 degrees, which is crucial for solving problems related to triangles and is a foundational principle in trigonometry and geometry used throughout further engineering studies and applications.

The other options represent angles that do not correspond to any triangle configurations: 360 degrees would represent a full circle, 120 degrees is the sum of angles in certain geometric figures but not a triangle, and 90 degrees is the sum of angles in a right triangle only but not the total sum for all triangles. Hence, understanding that triangle angles always sum to 180 degrees is essential for anyone studying geometry or related fields.