Download 9 lp day 2 Similar polygons revised

SUBJECT
Geometry
UNIT TITLE Similarity
Topic: Similar Polygons Section 8.2PH/8.3 ML
Objective:


Identify similar polygons
Use similar polygons to solve real-life problems, such as making
an enlargement similar to an original photo.
Core Content for Assessment:
 MA-11-3.1.6 Students will apply the concepts of congruence and
similarity to solve real-world problems.
Materials/Resources:
 Warm up Questions
 Picture Enlargement Activity
 ruler, protractor, and a calculator
Warm Up/Bell Ringer/Do Now:
See attached
Procedures:
1. Warm up
2. Review homework from previous lesson
3. Define/discuss/give examples of:
a. Writing Similarity Statements
b. Comparing Similar Polygons
c. Comparing Photographic Enlargements
d. Using Similar Polygons
4. Practice
a. Distribute Picture Enlargement Worksheet with two
pictures
b. Distribute rulers and protractors
c. Working in pairs have students complete worksheet
d. Review results
5. Summary/wrap up
6. Assignment homework
Lesson Assessments:
 Students will have a formative assessment throughout the class
when they are working on the in class practice worksheet

Students’ summative assessment will take place when their
homework is graded.
Bell Ringer/Warm Up
Transparency Available out of resource book (ML)
Find the measure of the angles in the below figure
U
V
61°
58°
W
1. Angle U
2. Angle W
Solve each proportion
3.
2 5

x 20
4.
18 12

5
x
Activity: Picture Enlargements
Measurement Photo 1
AB
AC
BC
mA
mB
Perimeter of
photo
Photo 2
Ratio
1. Measure each segment, angle, and perimeter of the photos.
Record your data in the chart above.
2. Find the ratio for each set of measurements of photo 1 to
photo 2.
3. What conjecture can you make about the ratio of sides?
4. What conjecture can you make about the ratio of angles?
5. What conjecture can you make about the ratio of perimeters?
6. Use your conjectures in 3 – 5 to describe properties of similar
figures.
Entrance to the Louvre (Paris, France)
Photo 1
Photo 2