Interior & Exterior Angles of Triangles Flashcards
The angle sum theorem states…?
the three interior angles of any triangle add up to 180 degrees.
The exterior angle theorem states…?
An exterior angle of a triangle is equal to the sum of the opposite interior angles.
The picture shows what theorem? Angle sum theorem or exterior angle theorem?
The Angle Sum Theorem
The picture shows what theorem? Angle sum theorem or exterior angle theorem?
The Exterior Angle Theorem
Given the measure of two interior angles of a triangle, how do you find the third interior angle?
Since the angle sum theorem tells us all three interior angles add to 180, we would subtract the two given angles from 180 to find the third interior angle.
Find the missing angle of the triangle in the picture.
71
Find the missing angle of the triangle in the picture.
36
Find the missing angle of the triangle in the picture.
80
Find the missing angle of the triangle in the picture.
105
How would you set up the equation to solve for x in the given picture?
You would take each of the expressions given in the triangle and add them together then make all of them equal 180. Like this: 3x+2+2x+12+x=180
How can you find an exterior angle if you know the measure of the two interior angles opposite from it?
You could add the two interior angles that are opposite from the exterior angle, and that would be what the exterior angle equals.
How can you find one of the opposite interior angles from the exterior angle, if you know one of the interior angles and the exterior angle? For example, look at the picture.
You would subtract the one interior angle you know from the measure of the exterior angle to find the other interior angle.
Find the missing angle of the triangle in the picture.
103
Find the missing angle of the triangle in the picture.
105
Find the missing angle of the triangle in the picture.
52