What is DF=
Help me please thank you :)

The value of DF = 20.
Two objects are similar if they have the same shape, or one has the same shape as the mirror image of the other.
Given:
Using theorem
If two triangles are similar, then the ratio of the area of both triangles is proportional to the square of the ratio of their corresponding sides.
ΔSDF/Δ RTY = (SD/RT)= (DF/TY)= (FS/ YR)
ar ΔSDF² / ar ΔRTY² = 16/81
SD/ RT = 4/9
SD = 4x, RT= 9x
SD= 8
4x = 8
x = 2
So,
RT= 9*2 = 18
SF = RT -2
SF = 16
(SD/RT)= (FS/ YR)
8 / 18 = 16/ YR
YR= 36
TY= 9 +RY = 45
(DF/TY)= (FS/ YR)
DF / 45= 16/ 36
DF=20
Learn more about similarity here:
https://brainly.com/question/25882965
#SPJ1