Предмет: Математика, автор: chaos2001

решите систему уравнений {xy= 16 {y/x= 4

Ответы

Автор ответа: Guppy2016
0
ху=16
у/х=4
из первого уравнения выразим Х
х=16/у(подстановка)
подставим во второе
у/(16/у)=4
y^2/16=4
y^2=16*4
y^2=64
у= корень из 64
у1=8, у2=-8
подставим эти значения в подстановку
х1=16/8
х1=2
х2=16/-8
х2=-2
ответ пары чисел (8 и 2) и (-8 и -2)
Автор ответа: Udmi99Taf
0
Из первого уравнения выразим х: х =  frac{16}{y} ; и подставим во второе уравнение:  frac{y}{x}  = 4 ;  frac{y}{ frac{16}{y} } = 4 ;  frac{ y^{2} }{16} = 4 y^{2} = 64 y₁ = 8, у₂=-8 x₁ =  frac{16}{y} =  frac{16}{8} = 2. х₂ =  frac{16}{y} =  frac{16}{-8} = -2. Ответ: (х₁=2; у₁=8); (х₂=-2; у₂=-8)
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