1. Ch.7.5_TrianglesProportionalSegments.notebook January 10, 2012
Chapter 7.5
Triangles and Proportional Segments

2. Ch.7.5_TrianglesProportionalSegments.notebook January 10, 2012
Segment connecting the midpoints of 2 sides
is one half the length of the third side
If
then
x
2x
3 4
2
3 4
x
5
9 5
y
4 4

3. Ch.7.5_TrianglesProportionalSegments.notebook January 10, 2012
If 2 triangles are ~, then:
their altitudes are in proportion
their medians are in proportion
median
altitude
Ex: Δ ABC ~ Δ DEF
A
D
18 12 x
12
B E F
C

4. Ch.7.5_TrianglesProportionalSegments.notebook January 10, 2012
If an altitude in a right triangle is drawn
to the hypotenuse then:
the 2 new Δ's are ~ to the big one
the 2 new Δ's are ~ to each other
B hypo
X t enus
e
C
B A
X
X
C
A
A
Solve for x S
10
R x W T
25

5. Ch.7.5_TrianglesProportionalSegments.notebook January 10, 2012
4
10
x 4
3 3
6.7
4
x
1
6 2