Question

19. If 4 + 2(3x - 4) = 8, then 4x - 4 =

Answer 1

4 + 2(3x - 4) = 8

Distributing in the second term:

`\begin{gathered} 4+2\cdot3x+2\cdot(-4)=8 \\ 4+6x-8=8 \\ 6x-4=8 \end{gathered}`

Multiplying by 4/6 at both sides, we get:

`\begin{gathered} (4)/(6)(6x-4)=(4)/(6)\cdot8 \\ (4)/(6)\cdot6x-(4)/(6)\cdot4=(32)/(6) \\ 4x-(16)/(6)=(16)/(3) \\ 4x-(8)/(3)=(16)/(3) \\ 4x=(16)/(3)+(8)/(3) \\ 4x=(24)/(3) \\ 4x=8 \end{gathered}`

Subtracting 4 at both sides:

`\begin{gathered} 4x-4=8-4 \\ 4x-4=4 \end{gathered}`

Then, 4 is the correct choice