Similar Polygons:
Q: Why were the similar
triangles weighing themselves?
SYMBOL for SIMILAR: ________
Corresponding angles are ______________________
Corresponding sides are _______________________
Writing Similarity Statements:
A: They were finding
their scale!
Corresponding <’s:
Proportional Sides: (statement of proportionality)
=
A BC
XYZ
=
=
If 2 polygons are _____________, then the ratio of the lengths of 2 corresponding
sides is called the ___________________.
What is the scale factor of ∆ABC to ∆XYZ? ________________
Practice:
1.) If polygon LMNO ~HIJK , completing proportions and congruence statements.
a. ∠M ≅ __?__
b. ∠K ≅ __?__
c. ∠N ≅ __?__
Hint: Draw a
diagram!!
d.
MN
IJ
?
HK
HI
IJ
=
e.
=
f.
JK
?
LM
MN
HK
?
2.) In the diagram, polygon ABCD ~ GHIJ.
A
11
D
8
x
x
B
G
y
H
5.5
11
C
J
8
I
a. Find the scale factor of polygon
ABCD to polygon GHIJ.
b. Find the scale factor of polygon
GHIJ to polygon ABCD.
c.
d. Find the perimeter of each polygon.
Find the values of x and y.
e. Find the ratio to the perimeter of ABCD to perimeter of GHIJ.
If 2 polygons are ___________, then the ratio of their perimeters is equal to the ratios
of their ____________________.
If 2 polygons are ___________, then the ratio of any two corresponding lengths in the
polygons is equal to their ____________________.
3.) The ratio of one side of ∆ABC to the corresponding side of similar ∆DEF is 3:5. The
perimeter of ∆DEF is 48in. What is the perimeter of ∆ABC?