Question

Помоготе сделать номер 8.

Answer 1

Объяснение:

$left { {{x=4+y} atop {frac{1}{y}-frac{1}{4+y}=frac{4}{5} }} right. \\left { {{x=4+y} atop {frac{4+y}{y(4+y)}-frac{y}{y(4+y)} = frac{4}{5} }} right. \left { {{x=4+y} atop {frac{4+y-y}{4y + y^{2} }= frac{4}{5} }} right.\\left { {{x=4+y} atop {frac{4}{4y+y^{2} } } =frac{4}{5}} right. \\left { {{x=4+y} atop {4y+y^{2} =5}} right. , y neq 0\left { {{x=4+y} atop {y^{2}+4y - 5 = 0 }} right.$$left { {{x = 4+ y} atop {y_{1} = -5, y_{2} = 1}} right. \\left { {{x_{1}= -1, x_{2} =5 } atop {y_{1} = -5, y_{2} = 1}} right. \Otvet: (-1;-5) (5;1)$