221

(-3, 0), (0, 1) ja (0, -3)

$\left(-3{,}\ 0\right)$
$y^2-x+2y-3=0$
$0-\left(-3\right)+2\cdot0-3=0$
$0+3+0-3=0$
$3-3=0$
$0=0$
$\left(0{,}\ 1\right)$
$1-0+2-3=0$
$3-3=0$
$0=0$
$\left(0{,}\ -3\right)$
$9-0+2\left(-3\right)-3=0$
$9-6-3=0$
$0=0$