chapter 7.2 similar polygons. vocabulary similar – two polygons are similar if – 1)...
TRANSCRIPT
Chapter 7.2 Similar Polygons
Vocabulary
• Similar – Two polygons are similar if– 1) Corresponding angles are congruent– 2) Corresponding sides are proportional
stands for similar~
Vocabulary
• Similarity ratio – the ratio of the lengths of corresponding sides of similar figures
• Example:
A
B C
D
E F
FD
CA
EF
BC
DE
AB
DEFABC ~
Vocabulary
• Golden rectangle – rectangle that can be divided into a square and a rectangle that is similar to the original rectangle
A B
CD F
E
ABCD is a rectangleADFE is a square
BCFEABCD ~
Vocabulary
• Golden ratio – the ratio of the length of a golden rectangle to its width. The value of the golden ratio is or about 1.62
2
51
Determining Similarity
• Determine whether the triangles are similar. If they are, write a similarity statement and give the similarity ratio
• Given: Corresponding angles congruent• Are the corresponding sides proportional?
A
B
C D
E
F18
1215
24
1620
DE
AB
EF
BC
DF
AC
Answer
• with similarity ratio of or 3:4 DEFABC ~4
3
ABCD~EFGH complete each statement
Em
AD
EF
AB
A
B C
D
E
F G
H
53
127
LMNO~QRST
• Find the value of xO
N
L M
T S
Q R
2
5
X
6
Classwork/Homework
• Pgs 375-376 1-16, 21-28