Geometry Vocab

lines in the same plane that never intersect; lines that never touch

• perpendicular lines

• parallel lines

• intersecting lines

• touching lines

perpendicular lines

• two lines that intersect at right angles

• an endless flat surface that is named by any three parts not in the same line

• lines that have exactly one point in common; lines that touch

• lines in the same plane that never intersect; lines that never touch

acute angle

• angle more than 90 degress

• angle exactly 180 degrees

• angle less than 90 degrees

• angle exactly 90 degrees

An angle exactly 90 degrees

• right

• acute

• obtuse

• straight

obtuse angle

• exactly 90 degree

• less than 90 degrees

• exactly 180 degrees

• an angle more than 90 degrees but less than 180 degrees

a closed plane figure with 3 or more sides

• shape

• polygon

• point

• circle

4-sided polygon

• quadrilateral

• triangle

• pentagon

• plane

5-sided polygon

• quadrilateral

• pentagon

• triange

• plane

a 7-sided polygon

• hexagon

• decagon

• heptagon

• pentagon

acute triangle

• a triangle with 3 acute angles

• a tringle with a 90 degree angle

• a triangle with 1 acute angle

• a triangle with an angle more than 90 degrees