When we add up the interior angle and exterior angle we get a straight line 180. For our equilateral triangle the exterior angle of any vertex is 120.

Triangles Unit Interior Angle Sum And Exterior Angle Remote

Then answer the questions that follow.

Interior angles and exterior angles. You may need to find exterior angles as well as interior angles when working with polygons. An interior angle of a polygon is an angle inside the polygon at one of its vertices. In this triangle x y and z are all interior angles.

For a square the exterior angle is 90. Be sure to change the locations of the pentagon s big black vertices each time before you drag the slider note. From the above diagram we can say that the triangle has three interior angles.

An interior angle is an angle inside the shape. An exterior angle of a triangle or any polygon is formed by extending one of the sides. Angle q is an interior angle of quadrilateral quad.

Show more show less. An exterior angle of a polygon is an. For interior angles you can make either the pink or green angle measure greater than 180 degrees if you d like.

The sum of the interior angles is always 180 implies x y z 180. Let us see the proof of this statement. In a triangle each exterior angle has two remote interior angles.

That s a mouth full. When two lines are crossed by a transversal the opposite angle pairs on the outside of the lines are alternate exterior angles. One way to identify alternate exterior angles is to see that they are the vertical angles of the alternate interior angles.

Interact with the applet below for a few minutes. In this video i am utilizing smart notebook and big ideas math to show examples of interior and exterior triangle angles. The exterior angle is the angle between any side of a shape and a line extended from the next side.

The points on the pentagon s sides are midpoints also note. Together the adjacent interior and exterior angles will add to 180. If the two lines are parallel then the alternate exterior angles are congruent.

The remote interior angles are just the two angles that are inside the triangle and opposite from the exterior angle.