Ответы и объяснения

2013-04-21T19:04:53+04:00
2013-04-21T19:06:33+04:00

9х=63                              4*-5=-20                     5*0=0                                  0*х=3

х=7                                   х=-5                              х=0                                      решения нет

9*7=63