Question

$\left \{ {2x + y = 5} \atop {3x + 8y = 12}} \right.$

Answer 1

Resposta:

$(x,y)=(\frac{28}{13},\frac{9}{13})$

Explicação passo-a-passo:

$\left \{ {{y=5-2x} \atop {3x+8y=12}} \right. \\3x+8(5-2x)=12\\x=\frac{28}{13} \\y=5-2.\frac{28}{13}\\y=\frac{9}{13} \\(x,y)=(\frac{28}{13},\frac{9}{13})\\\\\left \{ {{2.\frac{28}{13}+\frac{9}{13}=5  } \atop 3.\frac{28}{13}+8+\frac{9}{13}=12   \right. \\\\\left \{ {{5=5} \atop {12=12}} \right. \\(x,y)=(\frac{28}{13},\frac{9}{13})$

Espero ter ajudado!!