similarity and congruence
T
h
e
t
w
o
m
o
un
t
a
in
t
r
ia
n
g
l
e
s
a
r
e
t
h
e
s
a
m
e
s
h
a
p
e
,
b
u
t
r
e
s
ca
l
e
d
/
flipped
6060
37.5
30
40
48
40
6
60
41º 53º
To use similarity, you
need to be able to spot it
You won’t normally get instructions that
actually tell you that shapes are similar. So
in order to use similarity, first you need to
be able to be certain that shapes are similar.
You can do that by looking for matching sets
of angles.
T
he designer’s notes t
old
us the s
hap
es were similar.
Mou
ntain
tip tria
ngle
is the same
shape
tria
ngle as
the whole
mou
ntain
Circle the triangles below that you can be SURE are similar to the triangle repeated
in the design.
53
o
86
o
53
o
41
o
86
o
53
o
53
o
41
o
86
o
41
o
86
o
41
o
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