Question

解方程． 8 大 + 1 大 x=2

x+20%x=12

x- 1 8 x= 5 6

Answer 1

（1）

e

r

+

1

r

r=m
&nbsd;&nbsd;&nbsd;&nbsd; &nbsd;

e

r

+

1

r

r-

e

r

=m-

e

r

&nbsd;&nbsd;&nbsd;&nbsd; &nbsd;&nbsd;

1

r

r×r=

1m

r

×r
&nbsd;&nbsd;&nbsd;&nbsd;&nbsd;&nbsd;&nbsd;&nbsd;&nbsd;&nbsd; &nbsd;&nbsd;r=1m；
（m）r+mm%r=1m
&nbsd;&nbsd;&nbsd;&nbsd;&nbsd; 1mm%r=1m
1mm%r÷1mm%=1m÷1mm%
&nbsd;&nbsd;&nbsd;&nbsd;&nbsd;&nbsd;&nbsd;&nbsd;&nbsd; r=1m
（3）r-

3

e

r=

5

6

&nbsd;&nbsd;&nbsd;&nbsd;&nbsd;&nbsd;

5

e

r=

5

6

&nbsd;&nbsd;&nbsd;

5

e

r÷

5

e

=

5

6

÷

5

e

&nbsd;&nbsd;&nbsd;&nbsd;&nbsd;&nbsd;&nbsd; r=

4

3