Question

preciso do calculocalculo

Answer 1

$\left \{ {{x+2y=5} \atop {x+3y=8}} \right. \\ x+2y=5 \\ x=5-2y \\ \\ x+3y=8 \\ (5-2y)+3y=8 \\ 5-2y+3y=8 \\ -2y+3y=8-5 \\ y=3 \\ \\ x=5-2y \\ x=5-2.3 \\ x=5-6 \\ x=-1$
S = {-1,3}
Alternativa A.