Предмет: Математика, автор: мария1901

пожалуста решите уровнение дам 30 балов 3/7 х +(х - 3/7 х ) ×1/2 + 20 = х

Ответы

Автор ответа: bill14

3/7x+(x-3/7x)*1/2+20=x
3/7x+4/7x*1/2+20=x
3/7x+2/7x-x=-20
5/7x-x=-20
-2/7x=-20
2/7x=20
x=20*7/2
x=70

Автор ответа: мария1901

Спасибо большое

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