Answer :

arnfrs
1.75=12.3-x/2.8
x=(12.3-1.75)2.8
x=29.54
1.75 = 12.3 - x / 2.81.75-12.3=-x/2.8

-10.55=-x/2.8

-10,55*-2.8=x

x=29.54