Answer
$(x,y)|-2x+y=5$
Work Step by Step
$y=2x-5$
$8x-4y=20$
$y=2x-5$
$y-2x=2x-5-2x$
$-2x+y=-5$
$-2x+y=-5$
$8x-4y=20$
Please see the screenshot showing the steps for Cramer's rule.
Since we have zeroes for $D$, $D_x$, and $D_y$, we see that there are infinite solutions to the system.