Question

If EF = 4.2 cm, DF = 3.6 cm, and DE = 4.5 cm, what is CB?

Answer 1

QUICK ANSWER ON EDG - CB = 3.6 cm

Answer 2

the correct question in the attached figure

we know that
if the triangle ABC was rotated resulting in triangle EFD it implies that it retained it's original dimensions.

This means that ABC is proportional to EFD

hence
AB=EF-------> 4.2 cm
BC=FD-------> 3.6 cm
AC=ED------ > 4.5 cm

the answer is
CB=3.6 cm