5x+x+1=4.6 27-5x=3.5
①3x+5=17
②3x+0.2×6=3.6
③3(16.2﹣x)=19.2
④6x+1.5×0.7=1.41
1.5x=7.5 3.6x+2.4x=4.32 5(x-2.8)=30
4.5x+3.5x=64 42-7x=17.5 2(x+1.7)=25