3x-y=12 so y=3x-12.
8x/2y=4x/y=4x/(3x-12).
Or: x=(y+12)/3=⅓y+4 and 4x/y=(4y/3+16)/y=4/3+16/y.
The question is not very clear, so I'll try to interpret what you mean.
It's not clear what the small numbeers represent ("up on 8/4/2" makes no mathematical sense).
Upon 8/4/2 could mean:
a) 2/12
b) 4/4
c) 8/2
for the answer options.
a) If 8x/2y=4x/(3x-12)=2 then 4x=6x-24, 24=2x, x=12, y=3x-12=24. This links 2 with x=12.
b) If 8x/2y=4x/(3x-12)=4 then 4x=12x-48, 48=8x, x=6, y=3x-12=6. This links 4 with x=6
c) If 8x/2y=4x/(3x-12)=8 then 4x=24x-96, 96=20x, x=96/20=24/5, y=3x-12=12/5. This links 8 with x=24/5.
The only answer that in any way resembles any of the answer options is a, because 2 and 12 appear against this option.
The title of the question says 3-x=12, which makes x=-9, and there's no reference to y. If y=3x-12, then y=-27-12=-41, and 8x/2y=4x/y=-36/-41=36/41 (none of the answer options). The context of your question says 3x-y=12. Which is intended?
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