Geometry Basics

Front

What are vertical angles?

Back

Vertical angles are the angles opposite each other when two lines cross. They are equal in measure.

Front

What is the sum of the measures of supplementary angles?

Back

Supplementary angles total 180°.

Front

Define congruent shapes.

Back

Congruent shapes are identical in shape and size, though one shape can be rotated or flipped.

Front

What is a transversal in geometry?

Back

A transversal is a line that crosses two or more lines. If the crossed lines are parallel, the transversal creates two identical sets of four angles.

Front

What are complementary angles?

Back

Complementary angles are two angles whose measures add up to 90°.

Front

What is the difference between acute, obtuse, and right angles?

Back

An acute angle measures less than 90°, a right angle measures exactly 90°, and an obtuse angle measures more than 90° but less than 180°.

Front

What is the definition of parallel lines?

Back

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

Front

What are adjacent angles?

Back

Adjacent angles are two angles that share a common side and a common vertex but do not overlap.

Front

What is the relationship between alternate interior angles when two parallel lines are crossed by a transversal?

Back

Alternate interior angles are equal when two parallel lines are crossed by a transversal.

Front

What are corresponding angles?

Back

Corresponding angles are angles that are in the same position on two different lines when those lines are crossed by a transversal. They are equal if the lines are parallel.