geometry section 5.1 polygons their angle measures...2019/12/05 · geometry section 5.1 day 2...
TRANSCRIPT
Warm-up after 5.1 Day 1:1. Find the sum of the interior and exterior angles of a pentagon.
sum int. ∠s = ____ sum ext. ∠s = ____
2. The sum of interior angles of a convex polygon is 1080. Classify the polygon by its sides.
3. What is a regular polygon?
______________
Geometry Section 5.1Day 2
Polygons &
their angle measures
Learning Target:I can calculate angle measure for angles of polygons. [G.MG.1]
Review 5.1 Day 1Polygons• What 3 things do you need to check for to be a polygon?
• Can you classify a polygon by its sides?
• Equilateral, Equiangular, Regular
• Convex or concave?
• Sum of the interior angles = _______________________
where n is _________________________
• Sum of the exterior angles = _________
*ex - pentagon
xo
(x + 20)˚
112˚96o
2. Find the value of x.
1. Find the value of x. Hint: find the sum of the interior angles first
Hint: find the sum of the exterior angles first
3. Find the measure of one interior ∠ AND one exterior ∠ on a stop sign.
In a Regular Polygon,
Each Interior =
Each Exterior =
where n is the number of sides
4. If each exterior angle of a regular n-gon is 15˚,
then how many sides does the n-gon have?
5. Each interior angle of the regular n-gon has a measure is 162˚. Find the value of n.
OR
Homework:
Sum Interior = (n – 2) • 180
Sum Exterior = 360˚
In a Regular Polygon
Each Interior =n
(n – 2) •180
Each Exterior = n 360
Assignment: Finish 5.1 worksheet
Geometry 5.1 WS Answers1. 1440˚ 2. 4140˚
3. octagon 4. 20-gon
5. x = 53 6. x = 82
7. x = 117 8. x = 111
9. x = 66 10. x = 150
11. x = 36, largest angle =___ 12. x = ___ , smallest angle = 40
13. 1 int angle = 160˚ , 1 ext angle = 20˚
14. 40 sides 15. 15 sides
MUSTShow work#5-15!