Respuesta :

Answer:

x=9

Step-by-step explanation:

the ratio of triangleABC and DEF = 5:15 = 1:3

since these two triangles are similar, sideBC and EF's ratio is 1:3

therefore if BC is 3, then 3:9, so EF is 9

Answer:

x=9

i think that it is this try it