Question

Решите методом полстановки {y-4x=2 {xy-2x=8

Answer 1

$left { {{y-4x=2} atop {xy-2x=8}} right.$
$left { {{-xy+4x^2=-2x} atop {xy-2x=8}} right.$
$4x^2-2x=8-2x$
$4x^2=8$
$x^2=2$
$x= sqrt{2}$

$y=2+4x$
$y=2+4 sqrt{2}$
y≈8