Question

Resolva o seguinte sistema x + y = 10
x - y = 2

Answer 1

Olá.

$\mathsf{ \left \{ {{x+y=10} \atop {x-y=2}} \right. }\\\\\\x+y=10\ \therefore\ \boxed{x=10-y}\\\\\\x-y=2\\(10-y)-y=2\\10-2y=2\\-2y=-10+2\\-2y=-8\\y=\dfrac{-8}{-2}\\\boxed{\boxed{y=4}}\\\\\\x+y=10\\x+4=10\\x=10-4\\\boxed{\boxed{x=6}}\\\\\\\\\boxed{\boxed{\boxed{x=6\ \ \therefore\ \ y-4}}}$

Qualquer dúvida, deixe nos comentários.
Bons estudos.