## Triangle Sum Theorem

### The Triangle Sum Theorem, also known as the Angle Sum Theorem for triangles, states that the sum of the interior angles of a triangle is always equal to 180 degrees

The Triangle Sum Theorem, also known as the Angle Sum Theorem for triangles, states that the sum of the interior angles of a triangle is always equal to 180 degrees. In other words, the three angles of any triangle will always add up to 180 degrees.

To understand why this theorem holds true, let’s consider a triangle. We can divide it into two smaller triangles by drawing a line from one of the vertices to the opposite side. This line separates the larger triangle into two smaller ones.

Each of these two smaller triangles has an interior angle adjacent to the original triangle’s base. We know that the sum of the interior angles of these smaller triangles is also equal to 180 degrees because it is a property of triangles.

If we combine the two adjacent angles of the smaller triangles with the original triangle’s third interior angle, we will have all the interior angles of the larger triangle. Since the sum of the interior angles of both smaller triangles is equal to 180 degrees, when we combine them with the third angle, the total sum will still be 180 degrees. Hence, the Triangle Sum Theorem is proven.

This theorem is not limited to a specific type of triangle. It holds true for all triangles, whether they are equilateral (having three equal angles of 60 degrees each), isosceles (having two equal angles and two equal sides), scalene (having all three sides and angles different), or even right-angled (having one angle measuring 90 degrees).

The Triangle Sum Theorem is a fundamental concept in geometry and serves as a basis for many geometric calculations and proofs involving triangles. It helps in determining missing angles, identifying triangle congruence, and solving various problems related to polygons.

##### More Answers:

Understanding the Exterior Angle Theorem | Relationship Between Exterior and Interior Angles in a TriangleThe Importance of Interior Angles in Geometry | Exploring Definitions, Sum Formulas, and Calculations

Solving Geometry Problems | Understanding Exterior Angles in Polygons