9t+4t-286=0 помагите срочно
9t+4t-286=0 13t=286 t=286/13 t=22
9t+4t-286=0
13t-286=0
13t=286-0
13t=286
t=286-14
t=272
9t+4t-286=[9+4]t-286=13t-286