Answer/Step-by-step explanation:
Scale factor: 1/4
AC = DF and 10 ÷ 2.5 = 4
10 x 1/4 = 2.5
DE length: 5
AB = DE
20 x 1/4 = 5
BC length: 30
EF = BC
(Because EF is the dilation) 7.5 x 4 = 30