4×2.6-5x=8.4
10.4-5x=8.4
5x=10.4-8.4
5x=2
x=0.4
17.28-4x=5.6x
17.28=5.6x+4x
17.28=9.6x
x=17.28÷9.6
x=1.8
2（4x-3.5）=11
8x-7=11
8x=18
x=18÷8
x=2.25
4.3x-x+1.5x=9.6
(4.3-1+1.5)x=9.6
4.8x=9.6
x=9.6÷4.8
x=2