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解方程24x-8x=28.8 4.5x+1.6x=42.7 (7-1.4)x=2.8 9x-5.2×6=4.8 

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解方程
24x-8x=28.8

4.5x+1.6x=42.7

(7-1.4)x=2.8
9x-5.2×6=4.8          (2.5+x)÷0.8=5         0.5×(x-1.8)=2.4
8.9-5x=2.7            3.54×5-1.7x=13.45       1.6x+2x×0.7=18.
解方程24x-8x=28.8 4.5x+1.6x=42.7 (7-1.4)x=2.8 9x-5.2×6=4.8 
(1)24x-8x=28.8
        16x=28.8
    16x÷16=28.8÷16
          x=1.8;
(2)4.5x+1.6x=42.7
          6.1x=42.7
     6.1x÷6.1=42.7÷6.1
             x=7;
(3)(7-1.4)x=2.8
       5.6x=2.8
  5.6x÷5.6=2.8÷5.6
          x=0.5;
(4)9x-5.2×6=4.8
     9x-31.2=4.8
9x-31.2+31.2=4.8+31.2
          9x=36
       9x÷9=36÷9
           x=4;
(5)(2.5+x)÷0.8=5
(2.5+x)÷0.8×0.8=5×0.8
            2.5+x=4
        2.5+x-2.5=4-2.5
                x=1.5;
(6)0.5×(x-1.8)=2.4
0.5×(x-1.8)÷0.5=2.4÷0.5
            x-1.8=4.8
        x-1.8+1.8=4.8+1.8
                x=6.6;
(7)8.9-5x=2.7
8.9-5x+5x=2.7+5x
      8.9=2.7+5x
  8.9-2.7=2.7+5x-2.7
       5x=6.2
    5x÷5=6.2÷5
        x=1.24;
(8)3.54×5-1.7x=13.45
      17.7-1.7x=13.45
 17.7-1.7x+1.7x=13.45+1.7x
           17.7=13.45+1.7x
     17.7-13.45=13.45+1.7x-13.45
           4.25=1.7x
      4.25÷1.7=1.7x÷1.7
              x=2.5;
(9)1.6x+2x×0.7=18
     1.6x+1.4x=18
            3x=18
         3x÷3=18÷3
             x=6.