Пошаговое объяснение:
1)7(3-4*(-0,2))-5(3*(-0,2)+4=21-0,8+3+4=13,2
2)-2(3,1*0,8-1)+3(1,2*0,8+1)= -4,96+3*2,16= -4,2336
1)8.6 2)-23
1)7(3-4b)-5(3b+4)=7(3-4×(-0.2))-5(3×(0.2)+4)=7(3+0.8)-5(-0.6+4)=7×3.8-5×3.6=26.6-18=8.6
2)-2(3.1x-1)+3(1.2x+1)-8(0.3x+3)= -2(3.1×0.8-1)+3(1.2×0.8+1)-8(0.3×0.8+3)= -2(2.48-1)+3(0.96+1)-8(0.24+3)= -2×1.48+3×1.96-8×3.24= -2.96+5.88-25.92=2.92-25.92= -23
Пошаговое объяснение:
1)7(3-4*(-0,2))-5(3*(-0,2)+4=21-0,8+3+4=13,2
2)-2(3,1*0,8-1)+3(1,2*0,8+1)= -4,96+3*2,16= -4,2336
1)8.6 2)-23
Пошаговое объяснение:
1)7(3-4b)-5(3b+4)=7(3-4×(-0.2))-5(3×(0.2)+4)=7(3+0.8)-5(-0.6+4)=7×3.8-5×3.6=26.6-18=8.6
2)-2(3.1x-1)+3(1.2x+1)-8(0.3x+3)= -2(3.1×0.8-1)+3(1.2×0.8+1)-8(0.3×0.8+3)= -2(2.48-1)+3(0.96+1)-8(0.24+3)= -2×1.48+3×1.96-8×3.24= -2.96+5.88-25.92=2.92-25.92= -23