N1  13-100х=0                                       N2  8-0,8х=0                                       N3   7х-4=х-16                                      N4  1,3р-11=0,8р+5  

Вопрос от посетителя:

                                    N1
 13-100х=0
                                      N2
 8-0,8х=0
                                      N3
  7х-4=х-16
                                     N4
 1,3р-11=0,8р+5

 

Илюха отвечает:

13-100х=0

-100х=13-0

х=13/(-100)

х=-0,13
                                    
 8-0,8х=0

-0,8х=8-0

х=8/(-0,8)

х=10
                                     
7х-4=х-16

7х-х=-16+4

6х=-12

х=-12/6

х=-2
                                   

1,3р-11=0,8р+5

1,3р-0,8р=5+11

0,5р=16

р=16/0,5

р=32