Question

help me pleases!!!$\left \{ {{x+y=15} \atop {2x+3y=21}} \right.$

Answer 1

Boa Tarde!!!

$\left \{ {{x+y=15} \atop {2x+3y=21}} \right.$

y=15-x

2x+3(15-x)=21

2x-3x=21-45

-x=-24.(-1)

x=24

y=15-24

y=-9

S= {(24,-9)}