1. Bellwork

2. 5-3 & 5-4: Midsegments and Medians of Triangles
Rigor: Identify and apply theorems about medians and midsegments.
Relevance: center of gravity and indirect measurement

3. Triangle Midsegment Theorem
Midsegment Definition: The midsegment of a triangle connects the midpoints of 2 sides.
Theorem: The midsegment of a triangle is half the length of the side it is parallel to.

4. Example 1: Indirect Measurement
Calculate the distance across the base of the volcano and across the sink hole.
775m

5. Example 2: Calculate each measurementUW
mUWT RT . .

6. Example 3: Coordinate Geometry

7. Example 4: Calculate the value of n

8. 5-4 Honors Assignment Complete in Class!
Primary Assignment: join.quizizz.com
Codes:
Period
Period 5 –
Period 6 –
Secondary Assignment:
Workbook pg 213 #1 – 9, pg 214 ALL

9. 5-4 Standard Assignment Complete in Class!
Primary Assignment: join.quizizz.com
Codes:
Period
Period 4 –
Period 7 –
Secondary Assignment:
Workbook pg 213 #1 – 9, pg 214 #1, 4, 5, 6

10. Medians and Centroids
Median of a triangle – the segment from the vertex to the midpoint of the opposite side.
Centroid – the point of concurrency of the 3 medians
The centroid is always inside the triangle
FUN FACT! The centroid is also known as the triangle’s center of gravity because you could balance any triangular object from its centroid!

11. Ex 5: Center of Gravity
Below are plans for a triangular piece of a mobile. Where should the support be attached so the mobile is balanced?

12. The Centroid Theorem Easiest place to start is to find the small piece
Large piece = 2/3 length of median (Vertex to centroid)
Small piece = 1/3 length of median (Midpoint to centroid)
The small piece is 1/2 the length of the large piece. (the centroid partitions the median into a 1:2 ratio!)
Easiest place to start is to find the small piece

13. EX 6: Calculate the missing lengths
RS = 7. What is SL & RL?
b) NQ = 18. What is NS & SQ?
c) MS= 10. What is SP & MP?

14. 5- 3 Honors Assignments Primary Assignment: join.quizizz.com Codes:
Period 1: (due Thursday)
Period 5: (due Thursday)
Period 6: (due Friday)
Secondary Assignment:
Workbook pg 209 #1 – 4
Workbook pg 210 #1, 5, 6

15. 5- 3 Standard Assignments
Primary Assignment: join.quizizz.com
Codes:
Period 2: (due Friday)
Period 4: (due Friday)
Period 7: (due Friday)
Secondary Assignment:
Workbook pg 209 #1 – 4
Workbook pg 210 #1, 5, 6