1. Polygons Math 2A: [10-6] Polygons
Sunshine State Standards: MA.B , MA.C

2. Math 2A: [10-6] Polygons
»A polygon is a simple, closed figure formed by three or more straight lines.
»Examples:
»Non-Examples:
Sunshine State Standards: MA.B , MA.C

3. »Polygons are named by the number of sides they have.
Math 2A: [10-6] Polygons
3 Sides…
Triangle
4 Sides…
Quadrilateral
5 Sides…
Pentagon
Sunshine State Standards: MA.B , MA.C

4. 6 Sides… Hexagon 7 Sides… Heptagon 8 Sides… Octagon 9 Sides… Nonagon
Math 2A: [10-6] Polygons
6 Sides…
Hexagon
7 Sides…
Heptagon
8 Sides…
Octagon
9 Sides…
Nonagon
Sunshine State Standards: MA.B , MA.C

5. 10 Sides… Decagon n Sides… n-gon Ex: 21-gon
Math 2A: [10-6] Polygons
10 Sides…
Decagon
n Sides…
n-gon Ex: 21-gon
»A polygon that has all sides and angles congruent is called a regular polygon.
Sunshine State Standards: MA.B , MA.C

6. »Classify each polygon and state whether it is regular
»Classify each polygon and state whether it is regular. If it is not a polygon, explain why.
Math 2A: [10-6] Polygons
Sunshine State Standards: MA.B , MA.C

7. 1. A quadrilateral is a closed figure with four sides and four angles.
Math 2: [10-5] Quadrilaterals
1. A quadrilateral is a closed figure with four sides and four angles. 1.
The quadrilateral family tree: 6. 2. 3. 4. 5.
Sunshine State Standards: MA.C , MA.C , MA.C

8. 2. A parallelogram is a quadrilateral with two pair of parallel sides.
Math 2: [10-5] Quadrilaterals
3. A rectangle is a quadrilateral with four right angles.
Sunshine State Standards: MA.C , MA.C , MA.C

9. 4. A rhombus is a quadrilateral with 4 congruent sides.
Math 2: [10-5] Quadrilaterals
4. A rhombus is a quadrilateral with 4 congruent sides.
5. A square is a quadrilateral with 4 right angles and 4 congruent sides.
Sunshine State Standards: MA.C , MA.C , MA.C

10. 6. A trapezoid is a quadrilateral with 1 pair of parallel sides.
Math 2: [10-5] Quadrilaterals 1 2 3 4
The sum of the angles in any quadrilateral is always 360°.
= 360°
Sunshine State Standards: MA.C , MA.C , MA.C

11. Find the missing angles.
Math 2: [10-5] Quadrilaterals
Find the missing angles.
45°
55°
100° x°
118°
50°
80° y°
Sunshine State Standards: MA.C , MA.C , MA.C

12. »This formula can be used to find the angle sum of any polygon:
Math 2A: [10-6] Polygons
A = 180(n − 2)
Angle Sum
Number of Sides
A = 180(n − 2)
Divide by n to find each angle.
A = 180(4 − 2)
A = 180(2)
A = 360°
 4 = 90°
Sunshine State Standards: MA.B , MA.C

13. »Find the measure of each interior angle in a regular octagon.
Math 2A: [10-6] Polygons
Sunshine State Standards: MA.B , MA.C

14. »Perimeter is the distance around any polygon.
Math 2A: [10-6] Polygons
»What is the perimeter of this regular pentagon?
2.4 m
5 × 2.4 =
12 m
»A repetitive pattern of polygons that fit together with no overlaps or holes is called a tessellation.
Sunshine State Standards: MA.B , MA.C

15. Math 2A: [10-6] Polygons
BW: [10-6] Review
»Find the measure of each interior angle, round to the nearest tenth if necessary.
Regular dodecagon
(12 sides)
Regular undecagon
(11 sides) 34
Sunshine State Standards: MA.B , MA.C