Algebra Practice Test

The sum of the angles in a triangle is always 180 degrees, which is why this choice is the correct one. This fundamental property of triangles applies regardless of the type of triangle, be it an acute, obtuse, or right triangle.

When you create a triangle and measure each of its internal angles, you will consistently find that when you add them together, they total 180 degrees. This provides a basis for numerous geometric principles and applications, such as determining unknown angles or solving problems involving triangles in various contexts.

The other options do not align with this property; for instance, 90 degrees would be the angle measurements of a right triangle's acute angles, which is insufficient for a full triangle. The sum of 360 degrees applies to a full circle, while 120 degrees does not represent the angle sum in any triangle configuration. Recognizing that the angle sum of triangles is 180 degrees is essential for both basic geometry and more advanced mathematical concepts.