Geometry Vocabulary for Grade 10

Front

What is a point in geometry?

Back

A location in space with no size or dimension

Front

What is a line in geometry?

Back

A straight path extending in both directions with no end

Front

What is a plane in geometry?

Back

A flat surface extending infinitely in all directions

Front

What is a quadrilateral?

Back

A polygon with four sides

Front

What are parallel lines?

Back

Lines in a plane that never intersect

Front

What are perpendicular lines?

Back

Lines that intersect to form right angles

Front

What does congruent mean in geometry?

Back

Having the same size and shape

Front

What is an acute angle?

Back

An angle less than 90 degrees

Front

What is an obtuse angle?

Back

An angle greater than 90 degrees but less than 180 degrees

Front

What are complementary angles?

Back

Two angles whose sum is 90 degrees