This equation is not correct. Because,
\(4x+2(x+3)\quad =\quad 4x+2\cdot x+2\cdot 3=4x+2x+6=\quad 6x+6\)
And
\(6x+6\quad
eq \quad 8x+6\)
The only possible, solution for this equation would be, x=0. Because,
for x=0 :
\(4\cdot 0+2\cdot (0+3)=8\cdot 0+6=\quad 0+2\cdot 0+2\cdot 3=0+6\quad \Longrightarrow \quad 6=6\)