1. Unidad Didáctica 2
Proporcionalidad y semejanza.

2. 2

3. 3
a
b
=c
a
b
c
1
(Fig. 1)
a
1
=
c
b
a
1
=
b
a
a

4. 4
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A
B
c
D
= =K
c
= =K
A
1
/B
1
/D
a
b
c
d
=
a
b
b
c
=
(Fig. 2)
b
a b
c

5. 5
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A
B C




H
a + b
(Fig. 1)
A
B C




H
a - b
(Fig. 2)
a
c
c
b
=
a

6. 6
a =b
a.1=b.b
a
b
b
1
=
b
a
a
1
=b= a2
b.1=a.a
a

7. 7
L
R
.R
L
=
B
C
D
E
G
F
+ RR
L
b.h
2
h
2
L
b
h/2
L
=
A
C
h
h/2
bh/2
B
L
s

8. 8
3 cm
300 km
E= = =
3 cm
30000000 cm
1
10000000

9. 9
AB
A´B´
BC
B´C´
CD
C´D´
DA
D´A´
= = =

10. 10
O
O=A=(Fig.2)
(Fig.3)