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Polygons
• Two-dimensional
shapes that have
three or more sides
made from straight
lines.
• Examples:
–
–
–
triangles
squares
rectangles
Sides
• The lines you can
trace and count
on the outside of
a 2D shape.
• Example: A
triangle has 3
sides. A square
has 4.
Parallelogram
• A quadrilateral with
parallel opposite
sides of equal
length.
• Opposite angles are
equal.
Quadrilaterals
• Any twodimensional shapes
(polygon) with 4
straight sides and 4
angles
• The interior angles
of a Quadrilateral
add up to 360
degrees.
• Ex.
rhombus
rectangle
square
kite
trapezoid
Rectangle
• A 2D shape with 4
corners and 2 pairs of
opposite, equal,
parallel sides.
• The sides meet at
right angles.
Rhombus
• A 2D, four-sided
shape with opposite
sides that are parallel.
• All the sides are the
same length.
Rhombus
• A 2D, four-sided
shape with opposite
sides that are parallel.
• All the sides are the
same length.
• Diagonals of a
Rhombus bisect each
other at right angles.
Trapezoid
• A 2D shape (polygon)
with four sides.
• One pair of sides is
parallel.
Trapezoid
• A 2D shape (polygon)
with four sides.
• One pair of sides is
parallel.
Square
• 2D shape (polygon)
with 4 equal sides
and 4 right (90°)
angles.
• Opposite sides are
parallel.
Triangle
• Two-dimensional
shape (polygon)
with three straight
sides and three
angles.
• The interior angles
of a triangle add up
to 180 degrees.
• There are
–
–
–
–
isosceles triangles,
right triangles
equilateral triangles
scalene triangles
Isosceles Triangle
• A triangle with
2 equal sides
and 2 equal
angles
Equilateral Triangle
• A triangle with
3
equal sides and 3
equal angles.
Right Triangle
• A triangle with one
right angle (90
degrees).
Scalene Triangles
• A triangle with 3
different side
lengths and 3
different angle
measures.
Congruent
• Two figures are
congruent if they
have the same
shape and size.
• Two angles are
congruent if they
have the same
measure.
Rectangular Prism
• A 3D shape that has:
– 6 rectangular faces
• 2 of those faces are
equal
– 12 edges
– 8 vertices
•
•
•
•
Some faces are parallel
Some edges are parallel
Some faces are perpendicular
Some edges are perpendicular
Pyramid
• A three-dimensional
shape which has a
polygon for its base
and triangular faces
which meet at one
point (vertex).
Cube
• A three-dimensional
shape which has 6
square faces all the
same size, 12 edges
and 8 vertices.
• Some faces parallel
• Some edges parallel
• Some faces
perpendicular
• Some edges
perpendicular
Line
• An infinitely
long, thin, twodimensional
mark
• It has no
endpoints.
Line Segment
• A section of line
bounded by two
endpoints.
• A line segment
is not
continuous.
Intersecting
• Crossing over one
another.
• These lines are
intersecting.
Parallel
• Lines that are the
same distance apart
from each other.
• These type of lines
stay the same
distance apart for
their whole length.
They do not need to
be straight or the
same length.
• They never intersect.
Perpendicular
• Lines that intersect at
a perfect right angle
(90º) to one another.
• In solid shapes,
edges could be at a
right angle to one
another.
• Faces could also be
at right angles to one
another.
Angles
• A shape formed
by two lines or
rays that extend
from a common
point (vertex).
• The amount of
turning between
two lines that
meet at a
common point
(vertex).
Vertex (angles)
• The common
point between
two or more
rays or line
segments.
Right Angle
• An angle whose
measure is
exactly 90
degrees.
Symmetry
• An object is
symmetrical
when you can
fold it in half and
the two halves
are congruent.
• One half is a
mirror image of
the other.
Symmetrical
Not Symmetrical