12 x-7 при x=0,05
3-1,5x при x=-1/3
(2x-y ) :(x-3y ) при x-1 ,y=1/3

а) 12х-7 = 12*0,05-7 = 0,6-7 = -6,4
б) 3-1,5х = 3-1,5*(-1/3) = 3-3/2*(-1/3) = 3+1/2 = 3 1/2 = 3,5
в) (2х-у):(х-3у) = (2*(-1)-1/3):(-1-3*1/3) =
-2 1/3:(-2) = -7/3*(-1/2) = 7/6 = 1 1/6