Respuesta :

Answer:

28

Step-by-step explanation:

▪︎ ADE and ABC are similar triangles (AAA)

▪︎ DA = DB + BA = 30 + 12 = 42

▪︎ k = DA / BA = 42 / 12 = 3.5

▪︎ DE = BC * k = 8 * 3.5 = 28