Interior Angles Of A Triangle
More Lessons for Geometry
In this lesson, we will learn
- the interior angles of a triangle
- the properties of the interior angles of a triangle
- how the properties can be used to find the missing angles inside a triangle.
- how the sum of interior angles of a triangle can be used to set up equations.
The interior angles of a triangle are the angles inside the triangle
Properties of Interior Angles
- The sum of the three interior angles in a triangle is always 180°.
- Since the interior angles add up to 180°, every angle must be less than 180°.
Find missing angles inside a triangle
Find the value of x in the following triangle.
x + 24° + 32° = 180° (sum of angles is 180°)
x + 56° = 180°
x = 180° – 56° = 124°
The following video shows another example of
how to find the missing angle inside a triangle.
Using Interior Angles of Triangle to set up equations
How to use the sum of the interior angles of a triangle to solve problems
Using the sum of the interior angles of a triangle, write an equation and solve for the unknown
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