Предмет: Математика, автор: eldubenok

Решите систему уравнений !!!! x+ y= 12 x=3y

Ответы

Автор ответа: Shricke2

8

x+y=12
x=3y
подставим 3y вместо x:
3y+y=12
4y=12
y=3
тогда x=3*3=9

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