Question

1/2{x-4(2y-3x)}

Answer 1

I assume there are meant to be brackets around 1/2.

If you are expanding and simplifying:
(1/2){x - 4(2y - 3x)}
= (1/2){x - 8y + 12x}
= (1/2){13x - 8y}
= (13/2)x - 4y
= 6.5x - 4y