Номер 523. 1)1/3х+1/х=4/15 2)1/х-1/7х=2/7 3)1/4х+1/х=5/16 4)1/х-1/9х=2/9 5)1/8х+1/х=3/8 6)1/х-1/5х=2/15

1/3х + 1/х = 4/15
1/3х + 3/3х = 4/15
4/3х = 4/15
3х = 4 : 4/15
3х = 4 * 15/4
3х = 15
х = 15 : 3
х = 5

1/х - 1/7х = 2/7
7/7х - 1/7х = 2/7
6/7х = 2/7
7х = 6 : 2/7
7х = 6 * 7/2
7х = 3 * 7
7х = 21
х = 21 : 7
х = 3

1/4х + 1/х = 5/16
1/4х + 4/4х = 5/16
5/4х = 5/16
4х = 5 : 5/16
4х = 5 * 16/5
4х = 16
х = 16 : 4
х = 4

1/х - 1/9х = 2/9
9/9х - 1/9х = 2/9
8/9х = 2/9
9х = 8 : 2/9
9х = 8 * 9/2
9х = 4 * 9
9х = 36
х = 36 : 9
х = 4

1/8х + 1/х = 3/8
1/8х + 8/8х = 3/8
9/8х = 3/8
8х = 9 : 3/8
8х = 9 * 8/3
8х = 3 * 8
8х = 24
х = 24 : 8
х = 3

1/х - 1/5х = 2/15
5/5х - 1/5х = 2/15
4/5х = 2/15
5х = 4 : 2/15
5х = 4 * 15/2
5х = 2 * 15
5х = 30
х = 30 : 5
х = 6