1. Polygons…
SOL5.13
GES
Mrs. Norman

2. Which Shapes Are Polygons? Why?
Not Polygons

3. What is a Polygon?
A polygon is a closed plane figure made up of line segments.
The names of common polygons tell how many sides the polygon has.
vertex 2 3 3 2 2
side 3 2 2 4 4 3 3 3 3 2 2 4 3 2
Triangle
(3 sides)
Quadrilateral
(4 sides)
Pentagon
(5 sides)
Hexagon
(6 sides)
Octagon
(8 sides)

4. What is a Regular Polygon?
Clue: What do these polygons have in common?
A regular polygon has sides of equal length and angles of equal measure
These are regular polygons 5 2 3 3 2 2 4 4 5 2 2 5 3 3 2 2 4 5 3 2
Triangle
(3 sides)
Quadrilateral
(4 sides)
Pentagon
(5 sides)
Hexagon
(6 sides)
Octagon
(8 sides)

5. Polygon Videos
BrainPop

6. Classifying Angles (Review)

7. Acute Angle An acute angle has a measure between 0° and 90°.
(a cute = little)

8. Right Angle
A right angle has a measure of 90°.
(square = right = 90°)

9. Obtuse Angle An obtuse angle has a measure between 90° and 180°.
(obtuse = obese)

10. Straight Angle A straight angle has a measure of 180°.
(straight = flat)

11. Classifying Triangles (Review)

12. Classifying Triangles
Equilateral triangle
All sides are the same (equal) length.
The sum total of every triangle = 180°
So, if all of the angles are the same…
3 ÷ 180° = 60°
Each of the three angles of an equilateral triangle is 60°

13. Classifying Triangles
Isosceles triangle
At least two sides are the same (equal) length. 4 4 6 4 4

14. Classifying Triangles
Scalene triangle
No sides are the same (equal) length. 9 2 7 9 2 7

15. Classifying Triangles
Right triangle
One angle is a right (90°) angle.
The sides have special names.
The legs are the two sides that form a right triangle
The third side is the hypotenuse
hypotenuse
hypotenuse
legs
legs

16. Classifying Triangles
Acute triangle
All three angles are acute angles.

17. Classifying Triangles
Obtuse triangle
One angle is an obtuse angle.

18. Classifying Quadrilaterals

19. Classifying Quadrilaterals
How do you classify quadrilaterals?
Quadrilaterals can be classified by their
angles
pairs of sides.
Remember that a quadrilateral is any polygon with 4 sides.

20. Classifying Quadrilaterals
Types of quadrilaterals?
Parallelogram
Rectangle
Rhombus
Square
Trapezoid

21. Classifying Quadrilaterals
Parallelogram
A quadrilateral with both pairs of opposite sides
parallel
equal in length.
Parallelogram
Rectangle
Rhombus
Square

22. Classifying Quadrilaterals
Rectangle
A parallelogram with four right (90°) angles.
Rectangles & rhombuses are special parallelograms.
Rectangle
Square

23. Classifying Quadrilaterals
Rhombus
A parallelogram with all sides the same length.
Rectangles & rhombuses are special parallelograms.
Rhombus
Square

24. Classifying Quadrilaterals
Square
A rectangle with all sides the same length.
A square is a special rectangle. It is also a special rhombus.
Square

25. Classifying Quadrilaterals
Trapezoid
A quadrilateral with only one pair of parallel sides. A
Trapezoid
side A ll side C
side B ll side D D B C

26. ixl Classify Quadrilaterals
Quadrilateral Videos
ixl Classify Quadrilaterals

35. You now know all about Plane Figures!