Question

解方程．
x-0.6×5=10

8

9

+

1

9

x=2
x-70%x=1.26
1+40%x=2.8．

Answer 1

①x-0.6×5=10
x-3=10
x+3-3=10+3
x=13

②

8

9

+

1

9

x=2

8

9

-

8

9

+

1

9

x=2-

8

9

1

9

x×9=

10

9

×9
x=10


③x-70%x=1.26
0.3x=1.26
0.3x÷0.3=1.26÷0.3
x=4.2


④1+40%x=2.8
1+0.4x=2.8
1+0.4x-1=2.8-1
0.4x=1.8
0.4x÷0.4=1.8÷0.4
x=4.5