The complete question in the attached figure
we know that
length side AB=8 units
length side DE=4 units
[ABC]=[DEF]*[scale factor]
then
[scale factor ]=[ABC]/[DEF]---------> 8/4--------> 2
the answer is
the scale factor for a dilation image of DEF to obtain ABC is 2
we know that
length side AB=8 units
length side DE=4 units
[ABC]=[DEF]*[scale factor]
then
[scale factor ]=[ABC]/[DEF]---------> 8/4--------> 2
the answer is
the scale factor for a dilation image of DEF to obtain ABC is 2