Question

Determine o ponto de intersecção das retas r: 4x+y+5=0 e s: 2x-y+7=0

Answer 1

$\left \{ {{4x+y+5=0 \atop {2x-y+7=0}} \right.$
$6x=-12$
$x=-2$

$4.(-2)+y+5=0$
$-8+5=-y$
$y=3$

$P=(-2,3)$