Question

-4*(-0,8x+2y)-(4,2x-y) при x=2 y=-1

Answer 1

-4(-0,8х+2у)-(4,2х-у)=3,2х-8у-4,2х+у=-х-7у=-(х+7у)
-(2-7*1)=-(2-7)=-(-5)=5