Here is your answer
[tex]\bold{d. 12}[/tex]
REASON:
[tex]\frac{1}{2} x + 3= \frac{2}{3} x + 1[/tex]
[tex]\frac{2}{3} x-\frac{1}{2} x= 3-1[/tex]
[tex]\frac{4-3}{6} x= 2[/tex]
[tex]\frac{1}{6} x=2[/tex]
[tex]x= 6×2[/tex]
[tex]x= 12[/tex]
HOPE IT IS USEFUL