Download Polygons - Hobson Trudeau Team

Polygons
Vocabulary:
Vertex/verticies- a point at which two or more lines meet/intersect
Polygon- a closed plane (2-D or flat) figure with three or more sides that meet at verticies
Congruent- having equal measure; being the same size and shape
Regular Polygon- a polygon with congruent sides and angles (all angles and sides are the same
length)
Suffixes:
-lateral: sides
-gon: sides
Equi- : equal
Names of polygons:
# sides
Name
0
a point
1
a line
2
angle or intersecting lines
3
triangle
4
quadrilateral
5
pentagon
6
hexagon
7
heptagon
8
octagon
9
nonagon
10
decagon
Drawing
Angles
Acute angle- an angle that measures less than 90degrees
Obtuse angle- an angle that measures more than 90degrees
Right angle- an angle that measures exactly 90 degrees
Reflex angle- an angle that measures more than 180 degrees but less than 360 degrees
Straight angle- and angle of 180degrees (straight line)
Types of Triangles
Classified based on angles:
Right triangle- a triangle with ONE 90degree angle
Acute triangle- triangle with ALL acute angles (less than 90degrees)
Obtuse triangle- has ONE angle larger than 90degrees
Classified based on sides
Equilateral- all sides are congruent (the same length)
Isosceles- two sides are congruent (the same length)
Scalene- NO congruent sides (all different)
Quadrilaterals
Quadrilateral- a polygon with 4 sides, angles and verticies
Parallel- two lines that will never intersect (if they went on forever)
- two lines that will always measure the same distance apart
perpendicular- two lines that intersect to form right anlges
Types of Quadrilaterals:
parallelogram- opposite sides are parallel and congruent
rectangle- parallelogram with 4 right anlges
rhombus- parallelogram with all congruent sides
square- parallelogram: has two pairs parallel and congruent sides
rectangle- 90 angles
rhombus- all sides congruent
trapezoid- a quadrilateral with only ONE pair of parallel sides
3-Dimensional Figures
Polyhedron- a 3-D figure with sides that are polygons (prisms and pyramids are types)
Base- top or bottom face of a 3-D figure
Lateral face- the side faces of a 3-D figure
Prism- a polyhedron with 2 congruent polygons as bases
- the lateral faces of prisms are always rectangles
*The prism’s base shape is used to name the prism:
Base shape
prism name
Triangle
Rectangle
Pentagon
Hexagon
Heptagon
Octagon
Nonagon
Decagon
triangular prism
rectangular prism
pentagonal prism
hexagonal prism
heptagonal prism
octagonal prism
nonagonal prism
decagonal prism
Pyramid- a polyhedron with one base
The lateral faces are triangles
Pyramids are named by their bases:
Triangle
Rectangle
(etc.)
triangular pyramid
rectangular pyramid
Non-polyhedrons- have curved surfaces! And are NOT polyhedrons
Cylinder- two congruent circular bases connected with one curved face
Cone- has one circular base with one curved face that comes to a point
Sphere- NO base, one curved surface (in a ball shape)