-0,2x * (-5y)=0.2*5xy=xy
(-2x-4)*0.1= -2x*0.1 - 4*0.1= - 0.2x - 0.4
-5*(2-x)= - 10 +5x=5x -10
(4a-b) - 5a+3b=4a -b -5a+3b= -a+2b=2b -a
-(3x-0.4)+(0.4x-3)= - 3x+0.4+0.4x -3= - 2.6x - 2.6= -2.6(x+1)
9-2(x+1)+x=9 - 2x - 2+x=7-x
3(a-3b) - 5(a-2b)=3a - 9b - 5a+10b= -2a+b=b - 2a
при a= -1.5, b= -1
-1 - 2*(-1.5)= -1+3=2
0.4y-0.6(y-4)+2( -1+0.1y)=0.4y-0.6y+2.4-2+0.2y= - 0.2y+0.2y+0.4=0.4 - выражение не зависит от значения у
5а-(4а-(3а-2)=5а-4а -(3а-2)=5а-4а-3а+2= - 2а+2=2-2а=2(а-1)