分析:(1)先化简方程得x+15.9=19,再依据等式的性质,方程两边同时减去15.9求解;
(2)依据等式的性质,方程两边同时加上9.8,再同时除以3.2求解;
(3)依据等式的性质,方程两边同时减去18,再同时除以4.4求解;
(4)先化简方程得22.4-0.4x=20,再依据等式的性质,方程两边同时加上0.4x再减去20得0.4x=2.4,两边再同除以0.4求解;
(5)先化简方程得6.2x=18.6,再依据等式的性质,方程两边同时除以6.2求解.
解答:解:(1)x+5.3×3=19
x+15.9=19
x+15.9-15.9=19-15.9
x=3.1;
(2)3.2x-9.8=9.4
3.2x-9.8+9.8=9.4+9.8
3.2x=19.2
3.2x÷3.2=19.2÷3.2
x=6;
(3)18+4.4x=62
18+4.4x-18=62-18
4.4x=44
4.4x÷4.4=44÷4.4
x=10;
(4)4×5.6-0.4x=20
22.4-0.4x=20
22.4-0.4x+0.4x-20=20+0.4x-20
0.4x=2.4
0.4x÷0.4=2.4÷0.4
x=6;
(5)5x+1.2x=18.6
6.2x=18.6
6.2x÷6.2=18.6÷6.2
x=3.
点评:本题主要考查学生依据等式的性质解方程的能力,解答时注意对齐等号.