Question

Please help me Find DE.

Answer 1

DE is 11

Explanation:

`DE = DF - EF \\ DE = (4x + 2) - 7 \\DE = 4x - 5`

But for x:

`4x + 2 = (x + 7) + 7 \\ 4x + 2 = x + 14 \\ 3x = 12 \\ x = 4`

Therefore:

`DE = (4 * 4) - 5 \\ = 16 - 5 \\ = 11`

Answer 2

DE = 11

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