Respuesta :

You are given similarity. At this stage the diagram will tell you which sides correspond to which sides.

AC / DF = BC / EF
3 / 5 = 8 / 2x                     Cross multiply
3 * 2x = 5 * 8                    Multiply
6x = 40                             Divide by 6
x = 40 / 6
x = 6 4/6
x = 6 2/3 
6 2/3  answer <<<<<<<