D. 16
Cross multiply, to cancel the denominator; so if you multiple by 6 on one side, to cancel the division of 6 - you must also multiply the other side by 6 & vice versa.
You get:
8(x-4) = 6x
Expand bracket to get:
8x - 32
Now solve for x :
8x - 32 = 6x
- 8x
- 32. = - 2x
÷ - 2
16 = x
Or
8x - 32 = 6x
+ 32
8x. = 6x + 32
- 6x
2x. = 32
÷2
x =16
Check:
16 - 4 = 12, then ÷ 6 is 2
16/8 = 2
Hope this helps!