解方程: 2.7×2-1.5x=0 13x-6.8x+x=46.8 2.6x-6.5+3.5=10 2×(x-0.7)=4.8.
问题描述:
解方程:
2.7×2-1.5x=0 | 13x-6.8x+x=46.8 | 2.6x-6.5+3.5=10 | 2×(x-0.7)=4.8. |
答
(1)2.7×2-1.5X=0,
5.4-1.5X=0,
5.4-1.5X+1.5X=0+1.5X,
1.5X=5.4,
X=3.6;
(2)13x-6.8x+x=46.8,
7.2x=46.8,
7.2x÷7.2=46.8÷7.2,
x=6.5;
(3)2.6x-6.5+3.5=10,
2.6x-3=10,
2.6x-3+3=10+3,
2.6x=13,
2.6x÷2.6=13÷2.6,
x=5;
(4)2×(x-0.7)=4.8,
2x-2×0.7=4.8,
2x-1.4=4.8,
2x-1.4+1.4=4.8+1.4,
2x=6.2,
2x÷2=6.2÷2,
x=3.1.