3х³=48х
3х³-48х=0
3х(х²-16)=0
3х=0 или х²=16
х=0 или х=4
Ответ 0;4
9 2/7 = (9*7 + 2)/7 = 65/7
1 7/9 = (1*9 + 7)/9 = 16/9
2 2/5 = (5*2 + 2)/5 = 12/5
1 1/3 = (1*3 + 1)/3 = 4/3
65/7 + 16/9 : (12/5 - 4/3) * 3/7 =
= 65/7 + 16/9 * 15/16 * 3/7 =
= 65/7 + 15/21 =
= 195/21 + 15/21 =
= 210/21 = 10