Vă rog! ! ! ! ! ! ! ! ! ! Punctul a

a=-1,34-(-2,82)-(-1,285)=-1,34+2,82+1,285 = 2,765
b=-0,123-(-0,326)-(+0,264)=-0,123+0,326-0,264 = -0,061
c= -0,165-(+2,425)-(-3,128)-(+0,148)=-0,165-2,425+3,128-0,148 = 0,39
x=-a-(-b)-(-c)=-a+b+c=-2,765-0,061+0,39= -2,436
y=-a-(+b)-(-c)= -2,765+0,061+0,39= -2,314
x-y=-2,436-(-2.314)=-2,436+2,314= -0,122