3.2.2 Angle properties with triangle

There are several important angle properties that apply to triangles

• Angle sum property:

• The sum of the interior angles of a triangle is always \( 180 \) degrees. This means that the three angles of any triangle add up to \( 180 \) degrees.

• Exterior angle property:

• The measure of an exterior angle of a triangle is equal to the sum of the measures of the two interior angles that are not adjacent to it.

• Isosceles triangle property:

• In an isosceles triangle, the two base angles (the angles opposite the equal sides) are congruent (have the same measure).

• Equilateral triangle property:

• In an equilateral triangle, all three angles are congruent and each measure \( 60 \) degrees.

• Right triangle property:

• In a right triangle, one angle measures \( 90 \) degrees and the other two angles are complementary (add up to \( 90 \) degrees).

These properties can be used to solve problems involving angles of triangles.