Geometry Vocabulary

polygon- a closed figure formed by 3 or more line segments quadrilateral- polygon with 4 sides and 4 angles rhombus- a parallelogram with 4 congruent sides rectangle- a parallelogram with 4 right angles square- a polygon with 4 equal sides trapezoid- a quadrilateral with exactly one pair of parallel sides hierarchy- a system for organizing things attribute-a characteristic of a shape

triangle- polygon with 3 sides and 3 angles right triangle- triangle with one 90 degree angle acute triangle- triangle with 3 angles measuring less than 90 degrees obtuse triangle- triangle with one angle greater than 90 degrees equilateral triangle- all 3 sides are congruent (equal) scalene triangle- no sides are congruent (equal) isosceles triangle- 2 sides are congruent (equal)

regular polygon- all sides and angles are congruent irregular polygon- not all sides and angles are congruent pentagon- a polygon with 5 sides hexagon- a polygon with 6 sides heptagon- a polygon with 7 sides octagon- a polygon with 8 sides nonagon- a polygon with 9 sides decagon- a polygon with 10 sides circle- a closed figure with all points on the figure the same distance from the center point

20 Sided Polygon- Icosagon

Review Vocabulary- two dimensional-shape that only has two dimensions (such as width and height) and no thickness parallel- lines that do not intersect perpendicular- 2 lines that intersect to form right angles congruent- having the same size and shape right angle- an angle that measures 90 degrees