Respuesta :

Answer:

DE = 11

Step-by-step explanation:

DE = x + 7

EF = 7

DF = 4x + 2

DF = DE + EF (segment addition postulate)

Substitute

4x + 2 = x + 7 + 7

4x + 2 = x + 14

Collect like terms

4x - x = -2 + 14

3x = 12

Divide both sides by 3

x = 12/3

x = 4

✔️DE = x + 7

Plug in the value of x

DE = 4 + 7

DE = 11