Angle Properties of Different Types of Triangles

Triangles can be divided into three main types, based on their sides and angles. Let’s take a look at each type!

1. Scalene Triangle

   • What it is: A scalene triangle has all sides that are different lengths.
   • Angle Facts: The angles in a scalene triangle are also different. No matter what, the total of the angles inside the triangle will always be 180 degrees.

2. Isosceles Triangle

   • What it is: An isosceles triangle has at least two sides that are the same length.
   • Angle Facts: The angles across from the equal sides are also equal.
   • If the equal sides are length a, and the angle between them is C, you can find the other two angles (A and B) with this formula: $A + B + C = 180^\circ$
   • For example, if A equals B, then we can say: $2A + C = 180^\circ$ Now to find A, we can rearrange it like this: $A = \frac{180^\circ - C}{2}$

3. Equilateral Triangle

   • What it is: An equilateral triangle has all three sides the same length.
   • Angle Facts: In an equilateral triangle, all angles are equal, and each one measures 60 degrees. We can add them up like this: $60^\circ + 60^\circ + 60^\circ = 180^\circ$

Summary

No matter what type of triangle it is, all of them follow the important rule that the total of the angles inside adds up to 180 degrees. Knowing these properties is super important for solving different geometry problems in 7th-grade math!