Объяснение:
1) 5х+3х+7х=45
х=3
Стороны: 15, 9, 21
2) 3х=5 5х= = 8
7х = = 11
Стороны: 5, 8 , 11
3) 7Х=7
Стороны: 5, 3, 7
Объяснение:
1) 5х+3х+7х=45
х=3
Стороны: 15, 9, 21
2) 3х=5 5х=
= 8
7х =
= 11
Стороны: 5, 8
, 11
3) 7Х=7
Стороны: 5, 3, 7