Question

metodo de adição x+y=48 x-3y=16

Answer 1

$\left \{ {{x+y=48} \atop {x-3y=16}} \right.$
$\left \{ {{x+y=48 * (+1)} \atop {x-3y=16 * (-1)}} \right.$
$\left \{ {{x+y=48} \atop {-x+3y=-16}} \right.$
---------------------------------
+x-x+y+3y=48-16
4y=32
y=32/4
y=8