Geometry Unit 2 Mastery Vocabulary

Front

What is a line?

Back

A line is a straight path that goes on forever in both directions. It has no endpoints and is often named with two points on it, like line AB.

Front

What does congruent mean in geometry?

Back

Congruent shapes or angles are exactly the same in size and shape. If you could pick one up and place it on the other, they’d match perfectly.

Front

What is a midpoint?

Back

The midpoint is the point exactly in the middle of a segment, splitting it into two equal parts.

Front

What are complementary angles?

Back

Complementary angles are two angles whose measures add up to 90 degrees. For example, a 30-degree angle and a 60-degree angle are complementary.

Front

What is a segment?

Back

A segment is a part of a line with two endpoints. Think of it as a straight piece of string that starts at one point and stops at another.

Front

What is a ray?

Back

A ray is a part of a line that starts at one point and extends infinitely in one direction.

Front

What are vertical angles?

Back

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

Front

What is a polygon?

Back

A polygon is a closed figure formed by a finite number of straight line segments. Examples include triangles, quadrilaterals, and pentagons.

Front

What is the sum of the interior angles of a triangle?

Back

The sum of the interior angles of a triangle is always 180 degrees.

Front

What is a right angle?

Back

A right angle is an angle that measures exactly 90 degrees.