Transcript 1.5 Polygons

Polygons
1.5
Homework Review
Mental Math
Please take out your Fact Triangles.
Spend the next 5 minutes practicing your Fact Triangles
and sorting them.
Once you’ve sorted, focus on your TRY AGAIN pile.
When you are finished, fasten the pile with paper clips
and store them until our next practice session.
Math Message
Take your baggie of straws and twist-ties.
Make a shape with 5 sides.
• Work in your groups to create polygons
with 6 straws, 7 straws or 9 straws.
• What are the names of these polygons?
Convex and Concave (nonconvex)
A polygon in which all vertices are pushed outward is called a convex polygon.
A polygon in which at least one vertex is pushed inward is called a conCAVE polygon.
At least
one side
CAVES in.
Math Journal practice
A polygon is a regular polygon if:
-all of the sides have the same length
-all of the angles are the same size
-the polygon is convex
An equilateral triangle is a regular
triangle – it has three equal sides and
three equal angles.
Math Boxes- Tonight’s hw.
Closure
• What did you learn about polygons today?
Describe at least 3 facts.
What is a pentomino?
• A pentomino is a shape that is formed with
5 square tiles arranged in such a way that
full sides touch full sides and all 5 tiles are
flat and can be seen.
• There is no overlapping.
• **A pentomino is not considered different if
it can be turned, flipped, or slid onto
another pentomino to form the same
shape and size.**
Congruent shapes are the same size and shape.
Tonight’s Homework