Question

If DE = x + 4, EF = 4, and DF = 9x, what is DE?

Answer 1

We have the next given information:

DE = x + 4

EF = 4

DF = 9x

Now, looking at the graph:

DE + EF = DF

Replacing:

(x+4)+4 = 9x

Solve for x:

x+4+4 = 9x

x+8 = 9x

8 = 9x-x

8 = 8x

x= 8/8

x= 1

Hence,

DE = x+ 4

DE= 1+ 4

DE = 5