Question

помогите решить систему
1/х-1/у=-4/5
х-у=4

Answer 1

$left { {{5y-5x=-4xy} atop {x-y=4}} right.$


$left { {{5y-20-5y=(-16-4y)*y} atop {x=4+y}} right.$


$left { {{4 y^{2}+16y-20=0} atop {x=4+y}} right.$


$D= sqrt{36} = 6^{2}$



$y_{1} = 1 y_{2} = -5$

$x_{1} =5 x_{2} =-1$