Transcript Lesson 8 MI/Vocab

• Solve problems involving similar triangles.
• indirect measurement
8.3 The student identifies proportional or nonproportional linear relationships in problem situations
and solves problems. (B) Estimate and find solutions
to application problems involving percents and other
proportional relationships such as similarity and
rates. 8.9 The student uses indirect measurement to
solve problems. (B) Use proportional relationships in
similar two-dimensional figures or similar threedimensional figures to find missing measurements.
Use Shadow Reckoning
TREES A tree in front of
Marcel’s house has a shadow
12 feet long. Marcel’s shadow
is 3 feet long. If Marcel is 5.5
feet tall, how tall is the tree?
Use Shadow Reckoning
tree’s shadow
Marcel’s shadow
12 ● 5.5 = 3 ● h
tree’s height
Marcel’s height
Find the cross products.
Multiply.
Divide each side by 3.
Simplify.
Answer: The tree is 22 feet tall.
Jayson casts a shadow that
is 10 feet long. At the same
time, a flagpole casts a
shadow that is 40 feet long.
If the flagpole is 20 feet tall,
how tall is Jayson?
A. 4.5 feet
B. 5 feet
C. 5.5 feet
0%
D
0%
C
0%
B
D. 6 feet
A
0%
A.
B.
C.
D.
A
B
C
D
Use Indirect Measurement
SURVEYING The two
triangles shown in the
figure are similar. Find
the distance d across the
stream.
Use Indirect Measurement
Write a proportion.
AB = 48, ED = d, BC = 60, and DC = 20
48 ● 20 = d ● 60
Find the cross products.
Multiply. Then divide each side by 60.
Simplify.
Answer: The distance across the stream is 16 meters.
SURVEYING The two triangles
shown in the figure are similar.
Find the distance d across the
stream.
A. 6 feet
1.
2.
3.
4.
B. 6.5 feet
0%
C. 7 feet
D. 7.5 feet
A
B
C
D
A
B
C
D