View
363
Download
0
Category
Tags:
Preview:
Citation preview
SHAPES!
Introduction to some basic polygons
What do you know already?
How many shapes can you think of off the top of your head?
Where have you seen these shapes before?
What is a polygon?
2 dimensional
Closed
Made of straight lines
Which of these are polygons?
No
Yes
No
Triangle
Any three sided polygon
Types of Triangles:
Acute
Obtuse
Right
Scalene
Isosceles
Equilateral
Lets learn about the different kinds
Looking at side lengths
Scalene
All three sides of the triangle are different length
Isosceles
Two of the sides on the triangle are the same length
Equilateral
All three sides of the triangle are equal
Looking at the angles
Acute
ALL of the angles in the triangle is acute (less than 90°)
Obtuse
One of the angles in the triangle is an obtuse angle (greater than 90°)
Right
There is one right angle (90°) in the triangle
Parallelogram
Four sided polygon
Opposite sides are parallel
Rectangle
Polygon
4 sides
4 right angles (90°)
Parallelogram
Square
Special type of rectangle
Four EQAUL sides
Four 90° angles
Parallelogram
Rhombus
Another parallelogram
Opposite sides are parallel
Four EQUAL sides
Which is a rhombus?
Trapezoid
Only one pair of opposite sides are parallel
Four sides
Polygon, but NOT a parallelogram
Pentagon
Polygon
5 sided
Regular Pentagon has 5 equal sides
Which on is the regular pentagon and which is just a pentagon?
Polygon
6 sided
Regular Hexagon has 6 sides of equal length
Hexagon
Click icon to add picture
http://minglearound.files.wordpress.com/2010/12/nuts-bolts-washers.jpg
Octagon
Polygon
Eight sides
Regular octagon has 8 sides of equal length
Photo taken by Jillian Carey
Decagon
Click icon to add picture
Polygon
Ten sided figure
Regular decagon has ten equal sides
Which one of these is the regular decagon?
Recommended