9.44 Chapter 9
When all the corresponding angles of two quadrilaterals are equal (AAAA)
or all of their corresponding sides are proportional, are they necessarily
similar? Let's explore in Class Activity 9.2.
Refer to the figure. Determine whether ABCDE + FGHIJ is true.
E
D
C
A
B
2 cm
4 cm
40° 70°
H
G
I
F
J
3 cm
5 cm
18
Instant Drill
➥ Ex 9D 17
Refer to the figure. Determine whether
ABCD + EFGH is true.
In EFGH,
+EGH = +FEG (alt. +s, FE # GH)
a +EHG = +FEG
` +EHG = +EGH
` EH = EG (sides opp. eq. +s)
= 4 cm
EF
AB = cm
cm
3
2 = 3
2
EH
AD = cm
cm
4
3 = 4
3
` EF
AB ! EH
AD
` ABCD + EFGH is not true.
A D
B C
3 cm
2 cm
E H
F G
3 cm
4 cm
Level 2
Example 18
Solution
ABCD and EFGH do not have
the property 'corresponding
sides are proportional'.
◀
From the given information,
can we say that each pair
of figures in (a) and (b)
must be similar figures?
c
a
e
-- = -- = -- = --b
f
c
g
d
h
a e
g
d
(a)
(b)
b h f