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(2013•甘州区模拟)解方程345x+1.2x=258-4.5x=31234x-0.95×4=8.53.5x÷7=3.5.

题目详情
(2013•甘州区模拟)解方程
3
4
5
x+1.2x=25
8-4.5x=3
1
2
3
4
x-0.95×4=8.5
3.5x÷7=3.5.
▼优质解答
答案和解析
(1)
   3
4
5
x+1.2x=25,
3
4
5
+1.2)x=25,
          5x=25,
       5x÷5=25÷5,
           x=5;
(2)8-4.5x=3
1
2

  8-4.5x+4.5x=3
1
2
+4.5x,
     3
1
2
+4.5x=8,
 3
1
2
+4.5x-3
1
2
=8-3
1
2

          4.5x=4.5,
     4.5x÷4.5=4.5÷4.5,
             x=1;

(3)
3
4
x-0.95×4=8.5,
        
3
4
x-3.8=8.5,
    
3
4
x-3.8+3.8=8.5+3.8,
            
3
4
x=12.3,
        
3
4
3
4
=12.3÷
3
4

               x=16.4;

(4)3.5x÷7=3.5,
3.5x÷7×7=3.5×7,
      3.5x=24.5,
 3.5x÷3.5=24.5÷3.5,
         x=7;