Question

x+y=1
4x+7y=10
Metodo da adiçao

Answer 1

$\left \{ {{x+y=1} \atop {4x+7y=10}} \right.$

$\left \{ {{4x+4y=4} \atop {4x+7y=10}} \right.$

$\left \{ {{-4x-4y=-4} \atop {4x+7y=10}} \right.$

$4x+7y-4x-4y=10-4$

$3y=6$

$y=\frac{6}{3}$

$y=2$

$x+y=1$

$x+2=1$

$x=1-2$

$x=-1$