Вопрос школьника по предмету Математика
Решите систему уравнений способом подстановки:
х/5-у/3=-0,6,
х/4+у/6=1.
Ответ учителя по предмету Математика
( Х /5 ) — ( у / 3 ) = — 0,6
( Х / 4 ) + ( у / 6 ) = 1
Решение
( 3х — 5у ) / 15 = — 9/15
( 6х + 4у ) = 24
3х = 5у — 9
6х = 10у — 18
10у — 18 + 4у = 24
14у = 24 + 18
у = 3
3х = 30 — 18
Х = 12 : 3
Х = 4
Ответ ( 4 ; 3 )
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