(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
1.5x÷1.5=5.4÷1.5
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
2×(x-0.7)÷2=4.8÷2
x-0.7=2.4
x-0.7+0.7=2.4+0.7
x=3.1;
(5)5.4÷(3.94+0.86)×0.8
=5.4÷4.8×0.8
=1.125×0.8
=0.9.