What is true about all triangles regardless of their type?

All triangles, regardless of their type—be it acute, right, or obtuse—have a fundamental property: the sum of the interior angles is always exactly 180 degrees. This is a foundational concept in geometry that applies to every triangle regardless of its shape or size.

Understanding this characteristic is essential for solving various geometric problems, and it serves as a foundational principle in both basic and advanced mathematics. The sum of the angles property also assists in establishing other principles, such as the relationships between angles and sides in triangles, and is instrumental in more complex fields like trigonometry.

In contrast, the other statements do not hold true for all triangles. For instance, one statement suggests that at least one angle is greater than 90 degrees, which only applies to obtuse triangles. Another states that all sides must be of equal length, which is a defining characteristic of equilateral triangles but not applicable to all. Similarly, the notion of angles summing to more than 180 degrees is fundamentally incorrect in the context of triangles. Therefore, recognizing that all triangles have angles summing to exactly 180 degrees is a crucial piece of geometric knowledge.