3x-y+1-(2y+(8x-4y))=3x-y+1-(2y+8x-4y)=3x-y+1-2y-8x+4y=4x+y-7= 4 ×(-3целых 2/12)+2ц2/9-7= 4×(-0.5)+0.4-7=-2+0.4-7=-1,6-7=-8.6
3x-y+1-(2y+(8x-4y))=3x-y+1-(2y+8x-4y)=3x-y+1-2y-8x+4y=4x+y-7= 4 ×(-3целых 2/12)+2ц2/9-7= 4×(-0.5)+0.4-7=-2+0.4-7=-1,6-7=-8.6