Triangle Sum Theorem
Exterior Angle Theorem
Parallel Lines/Transversals
Classifying Triangles
Vocab/
Theorems
Theorems
100
The sum of the interior angles of any triangle.
What is 180°?
100
Extending a side of a triangle forms this type of angle outside the triangle.
What is an exterior angle?
100
These lines in a plane never intersect.
What are parallel lines?
100
A triangle has side lengths 5 cm, 5 cm, and 8 cm.
What type of triangle is this by its sides?
Isosceles (two sides are equal).
100
A straight angle is _______ degrees.
180
200
True or False: The Triangle Sum Theorem applies to all triangles, including obtuse and right triangles.
What is True?
200
Define Exterior Angle Theorem
What is the exterior angle is equal to the sum of the two non-adjacent angles.
200
This line cuts across two or more other lines.
What is a transversal?
200
A triangle has angles measuring 30°, 60°, and 90°.
What type of triangle is this by its angles?
Right triangle (one angle is 90°).
200
A pair of angles that sum to 180 degrees.
Supplementary Angles, Linear Pair
300
If two angles of a triangle measure 50° and 60°, this is the measure of the third angle.
What is 70°?
300
If triangle PQR has interior angles P=64 degrees and Q=40 degrees, what is the exterior angle at R?
104 degrees
300
When a transversal crosses parallel lines, these angles are equal and lie in the same relative position at each intersection.
What are corresponding angles?
300
I am a triangle with a 104 degree angle and 3 different length sides.
Obtuse Scalene
300
This theorem states that the measure of an exterior angle of a triangle equals the sum of the two non-adjacent interior angles.
What is the Exterior Angle Theorem?
400
What is the value of b?
What is 45°?
400
True or False: An exterior angle of a triangle can be smaller than either of the non-adjacent interior angles.
What is False?
400
These angles lie outside the parallel lines but on opposite sides of the transversal and are equal.
What are alternate exterior angles?
400
I am a triangle with 60 degree angles.
Equilateral or Equiangular
400
The sum of the interior angles of a triangle sum to 180, what theorem am I?
Triangle Sum Theorem
500
Use the three angles to solve for x.
35, 90, 5x+10
9
500
If one exterior angle of a triangle measures 120°, and one non-adjacent interior angle measures 70°, this is the measure of the other non-adjacent interior angle.
What is 50°?
500
When a transversal crosses parallel lines, these interior angles on the same side of the transversal are supplementary.
What are consecutive interior angles (same-side interior angles)?
500
I am a triangle with a right angle and two congruent sides.
Right Isosceles
500
You are given an angle of 84, an angle of 24+x, and the last angle of 48+x. What does x equal?
12