Transcript 5.1 Midsegments of Triangles

Brett Solberg
AHS
’11-’12
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1) Find the distance between (1, 4) and (4,8).
2) Find the midpoint of the segment whose
endpoints are (4, 11) and (6, 3).
3) Find the slope of the line containing the
points (8, 3) and (7, 12).
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Chapter 5 Relationships Within Triangles
◦ Triangle Midsegments
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Test Make-up
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A line that connects two midpoints of two
sides of a triangle is called the midsegment
of a triangle.
DE is a midsegment
of ∆ABC
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What relationships did you discover between
a triangle midsegment and the third side of a
triangle?
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The midsegment of a triangle is half the
length of the third side of a triangle.
DE = 5
BC = 10
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The midsegment of a triangle is parallel to
the third side of a triangle.
DE || BC
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Which segments are parallel?
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M, N, and P are midpoint in ∆XYZ. The
perimeter of ∆MNP is 60. Find NP and YZ.
MN = 22 MP = 24
MN + MP + NP = 60
22 + 24 + NP = 60
NP = 14
XY = 28
YZ = 44
XZ = 48
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5.1 Worksheet
◦ pg 262 #1 – 13 all
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CD = 4 cm
CE = 8 cm
DE = 7 cm
MO =
NO =
NM =
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Find the value of the variable.
Perimeter of ∆ABC = 32 cm
n + 7/8n + 1/2n = 32
8n + 7n + 4n = 256
19n = 256
n = 13.47