Answer:
26cm
Step-by-step explanation: we want a triangle with shorter sides (smaller perimeter) and we got 2 similar triangles , since triangles are similar the corresponding sides would be in ratio.
To get triangle of shorter perimeter we have to use the longest side of
△
A
B
C
put 6cm side corresponding to 12cm side.
Let
△
A
B
C
~
△
D
E
F
6cm side corresponding to 12 cm side .
therefore,
A
B
D
E
=
B
C
E
F
=
C
A
F
D
=
1
2
So the perimeter of ABC is half of the perimeter of DEF .
perimeter of DEF =
2
×
(
3
+
4
+
6
)
=
2
×
13
=
26
c
m
answer 26 cm.
