Triangles and Parallel Lines Cut by a Transversal Flashcards
The interior angles of a triangle add up to how many degrees?
180 degrees
The word “alternate” in alternate interior angles refers to what characteristic?
The angles are on opposite sides of the transversal
The word “interior” in alternate interior angles refers to what characteristic?
The angles are inside the parallel lines
_______ ________ share a side and a vertex.
Adjacent angles
The word “adjacent” means “next to.”
________ ______ have measures that add up to 180 degrees.
Supplementary angles
For a triangle, every ______ _______ is supplementary to its adjacent interior angle.
exterior angle
In this example, angle ∠ACD is supplementary to ∠ABC
The measure of an interior angle is equivalent to the sum of the two ______ _______ ________.
remote interior angles
In this example, the measure of ∠ACD is equal to the sum of the measures of ∠BAC and ∠ABC.
∠BAC and ∠ABC are the remote interior angles of ∠ACD.
________ _______ are opposite angles that share the same vertex. They are formed by a pair of intersecting lines. Their angle measures are equal.
Vertical angles
________ _______ ________are created when two parallel lines are crossed by another line called a transversal. They are inside the parallel lines and on opposite sides of the transversal.
Alternate interior angles
In this image, which angle is congruent with angle 6 because it is the alternate interior angle?
3
In this image, which angle is congruent with angle 3 because it is a vertical angle with angle 3?
2
In this image, the measures of angles 5 and 6 must add up to what?
180 degrees
Together angles 5 and 6 form a straight angle. Straight angles measure 180 degrees.
