3 части - х,у,z.
130=x+y+z
2x=3y |:2 ; 2x=4z |:2
x=1,5y ; x=2z
Приравниваем:
1,5у=2z |: 2
z = 3y/4 = 0,75y
Итак
x = 1,5y
y = y
z = 0,75y
Составляем уравнение
1,5y+y+0,75y = 130
3,25y = 130 |:3,25
y = 40
x = 1,5y = 1,5*40 = 60
z = 0,75y = 0,75*40 = 30
Ответ: 30, 40, 60
2т+65ц=2000кг 6500кг
... ....... .
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-(8х+(х-6)-(-9х+14у)
-(8х+х-6)+9х-14у
-8х-х+6+9х-14у
6-14у
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X(805-787)=7(625+61)
18x=4375+427
18x=4802
x=4802:18
x=2401/9-266 целых семь девятых,т.е. 7/9.