Transcript WORLD OF SHAPES - Colorado School of Mines

WORLD OF SHAPES
Polygons and Geometry
Geometric Language
line
segment
point
ray
Naming Angles
An angle is formed by two rays that have a common endpoint.
obtuse
acute
right
straight
Naming Lines
Two lines on a flat surface are parallel if they do
not meet.
Naming Shapes
Mathematical terms like polygon can help you
describe designs clearly in just a few words.
polygons
not polygons
What are three rules all polygons must follow?
More Polygons
Regular polygons have equal or congruent sides that
for congruent interior angles.
All polygons that are not
regular are called irregular
polygons.
Naming Regular Polygons
Naming Irregular Polygons
A polygon with four sides is called a
quadrilateral.
A quadrilateral that has exactly one pair of parallel
sides is called a trapezoid.
A quadrilateral with two pairs of parallel sides is called a
parallelogram.
A parallelogram with all sides the same length is called a
rhombus.
Finding Lines of Symmetry
Line symmetry
not line symmetry
Some objects have more than one line of symmetry. Which
shapes above have more than one line of symmetry?
Examples