ANSWER
Given that Δ ABC ~ ΔDEF
solve for x
To proof
as given in the question
ΔABC ~ ΔDEF
this means their sides are proportional to each other.
thus
\(\frac{AB}{AC} = \frac{ED}{DF}\)
As given
AB = 30unit
AC = 24unit
ED = 5unit
DF = x
put in the above
\(x = \frac{5\times24}{30}\)
solving
x = 4 unit
option (C) is correct
Hence proved
