Triangles and Parallel lines with Transversals

Front

What is a triangle?

Back

A triangle is a polygon with three edges and three vertices. It is one of the basic shapes in geometry.

Front

What are parallel lines?

Back

Parallel lines are lines in a plane that never meet; they are always the same distance apart.

Front

What is a transversal?

Back

A transversal is a line that crosses at least two other lines in the same plane.

Front

What are alternate interior angles?

Back

Alternate interior angles are pairs of angles that are on opposite sides of the transversal and inside the two lines.

Front

What are corresponding angles?

Back

Corresponding angles are pairs of angles that are in the same position on two different lines cut by a transversal.

Front

What are vertical angles?

Back

Vertical angles are the angles opposite each other when two lines intersect. They are always congruent.

Front

What are supplementary angles?

Back

Supplementary angles are two angles whose measures add up to 180°.

Front

What are congruent angles?

Back

Congruent angles are angles that have the same measure.

Front

If two parallel lines are cut by a transversal, what can be said about the alternate exterior angles?

Back

Alternate exterior angles are congruent.

Front

If angle 2 is 70°, what is the measure of angle 6 if lines are parallel?

Back

Angle 6 is also 70° because they are corresponding angles.