Answer:
DE = 11
Step-by-step explanation:
DF = DF +EF
4x+2 = x+7 + 7
Combine like terms
4x+2 = x+14
Subtract x from each side
4x+2-x = x+14-x
3x+2 = 14
Subtract 2 from each side
3x+2-2 =14-2
3x=12
Divide by 3
3x/3 = 12/3
x = 4
DE = x+7 = 4+7 =11
DE is 11
[tex]DE = DF - EF \\ DE = (4x + 2) - 7 \\DE = 4x - 5 [/tex]
But for x:
[tex]4x + 2 = (x + 7) + 7 \\ 4x + 2 = x + 14 \\ 3x = 12 \\ x = 4[/tex]
Therefore:
[tex]DE = (4 \times 4) - 5 \\ = 16 - 5 \\ = 11[/tex]
