1/3х + 1/х = 4/15
5 + 15 = 4х
4х = 20
х = 20/4
х = 5
проверка 1 / 3*5 + 1 / 5 = 1/15 + 1/5 = 1/15 + 3/15 = 4/15 ; 4/15 = 4/15.
1/3х + 1/х = 4/15
5 + 15 = 4х
4х = 20
х = 20/4
х = 5
проверка 1 / 3*5 + 1 / 5 = 1/15 + 1/5 = 1/15 + 3/15 = 4/15 ; 4/15 = 4/15.