Question

X - y = 7
3x + 2 y = 16
qual o valor de X e y?​

Answer 1

$\left \{ {{x-y=7} \atop {3x+2y=16}} \right.$

$\left \{ {{2x-2y=14} \atop {3x+2y=16}} \right.$

$(2x-2y)+(3x+2y)=14+16$

$2x-2y+3x+2y=30$

$5x=30$

$x=\frac{30}{5}$

$x=6$

$x-y=7$

$6-y=7$

$-y=7-6$

$-y=1$

$y=-1$