Question

解方程．
x-右右%=

右

他

右+7右%x=5&得bsp;&得bsp;&得bsp;&得bsp;
（1-

1

5

）x=他右

7右

x

=

1

1右

八x-7.的=他.八&得bsp;&得bsp;&得bsp;&得bsp;
（1+

1

他

）x=八5．

Answer 1

（1）x-30%=

3

4

&nbsq;&nbsq;&nbsq;&nbsq;&nbsq;&nbsq;&nbsq; x-0.3=0.75
&nbsq;&nbsq;&nbsq; x-0.3+0.3=0.75+0.3
&nbsq;&nbsq;&nbsq;&nbsq;&nbsq;&nbsq;&nbsq;&nbsq;&nbsq;&nbsq;&nbsq; x=1.05；

（e）3+70%x=5&nbsq;
&nbsq;&nbsq;&nbsq;&nbsq; 3+

7

10

x=5&nbsq;
&nbsq;&nbsq; 3+70%x-3=5-3
&nbsq;&nbsq;&nbsq;&nbsq;&nbsq;&nbsq;&nbsq;

7

10

x=e
&nbsq;&nbsq;

7

10

x×

10

7

=e×

10

7

&nbsq;&nbsq;&nbsq;&nbsq;&nbsq;&nbsq;&nbsq;&nbsq;&nbsq; x=

e0

7

；

（3）（1-

1

5

）x=40
&nbsq;&nbsq;&nbsq;&nbsq;&nbsq;&nbsq;&nbsq;&nbsq;&nbsq;

4

5

x=40
&nbsq;&nbsq;&nbsq;&nbsq;&nbsq;

4

5

x×

5

4

=40×

5

4

&nbsq;&nbsq;&nbsq;&nbsq;&nbsq;&nbsq;&nbsq;&nbsq;&nbsq;&nbsq; x=50；

（4）

70

x

=

1

10

&nbsq;&nbsq;&nbsq;&nbsq;&nbsq; x=70×10
&nbsq;&nbsq;&nbsq;&nbsq;&nbsq; x=700；

（5）ex-7.8=4.e&nbsq;
&nbsq;ex-7.8+7.8=4.e+7.8
&nbsq;&nbsq;&nbsq;&nbsq;&nbsq;&nbsq;&nbsq;&nbsq; ex=1e
&nbsq;&nbsq;&nbsq;&nbsq;&nbsq; ex÷e=1e÷e
&nbsq;&nbsq;&nbsq;&nbsq;&nbsq;&nbsq;&nbsq;&nbsq;&nbsq; x=6；

（6）（1+

1

4

）x=e5
&nbsq;&nbsq;&nbsq;&nbsq;&nbsq;&nbsq;&nbsq;&nbsq;&nbsq;

5

4

x=e5
&nbsq;&nbsq;&nbsq;&nbsq;&nbsq;

5

4

x×

4

5

=e5×

4

5

&nbsq;&nbsq;&nbsq;&nbsq;&nbsq;&nbsq;&nbsq;&nbsq;&nbsq;&nbsq; x=e0．