Question

For #4 I’m not sure if I’m correct. Can anyone help?

Answer 1

DF = DE + EF

So,

DF = 47 + 3x +10

We know that DF = 9x - 39, so:

9x - 39 = 47 + 3x + 10

9x - 3x = 57 + 39

6x = 96

x = 16

EF = 3x + 10

EF = 3.16 + 10

EF = 48 + 10

EF = 58

It's fine :)