• Find the coordinates of the midpoint
• AB with A(-2,3) and b(4,1)
• Find the slope of the line containing each
pair of points
• A(-2,3) AND B(3,1)
• Theorem 5-1 (Midsegment Thm): The
segment that joins the midpoints of two sides
of a triangle (midsegment)
•
•
1. is parallel to the third side;
2. is half as long as the third side.
1
DE  BC
2
BC  2 DE
• EB = ½(CD) = ½(18) = 9
• BC = 10
• AC = 20
• Find x and the side x is contained in
•
•
•
•
5x – 2 = 2 x 4
5x – 2 = 8
5x = 10
x=2
D, F, and E are all midpoints of their sides
DF AC
FE BA
DE BC
• XP = PZ = MN = 24
• YN = NZ = MP = 22
• P = MP + NP + MN
60 = 22 + NP + 24
60 = 46 + NP
14 = NP
• YZ = YN + NZ
YZ = 22 + 22 = 44
• Find 𝒎∠𝑨𝑴𝑵 𝒂𝒏𝒅 𝒎∠𝑨𝑵𝑴
• This is an Isosceles Triangle, so use
your Isosceles Triangle Theorems.
• 𝒎∠𝑨𝑪𝑩 = 75
• Now use your parallel lines theorems
to find the other angles
• 𝒎∠𝑨𝑴𝑵 = 𝒎∠𝑨𝑵𝑴 = 𝟕𝟓 by
corresponding angles
• CD = ½ (2640)
• CD = 1,320 ft.
•Pg. 246-247 #1-19