Выразите в уравнений x через y и y через xa)2x-y=7b)-3x+5y=1 - Znanija.Site

Выразите в уравнений x через y и y через x
a)2x-y=7
b)-3x+5y=1
- Предмет:
  Алгебра
- Автор:
  giovanni121
- 5 лет назад

Ответы 1

а). у=2х-7
2х-(2х-7)=7
х=(7+у)/2
2× (7+у)/2 =7.
б). у=(1+3х)/5
-3х+5× (1+3х)/5 = 1
х= - (1-5у)/3
- Автор:
  miriamlowe
- 5 лет назад
- 0
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