If AABC ~ ADEF, what is the length of DE?

NEED HELP ASAP please and thanks In advance

DE = 21

Step-by-step explanation:

Recall: the ratio of the corresponding side lengths of similar triangles are equal

Given that ∆ABC ~ ∆DEF, therefore,

AB/DE = BC/EF = AC/DF

AB = 8.4

DE = x

BC = 10

EF = 25

AC = 16.5

DF = 41.25

Let's find DE using AB/DE = BC/EF. Thus:

8.4/x = 10/25

Cross multiply

x*10 = 25*8.4

10x = 210

Divide both sides by 10

x = 210/10

x = 21

DE = x = 21

not sure but it may be b, as i said i'm not sure.