Question

{9x-[4x-(x-y)-5y]+y} Alguem sabe reposta ?

Answer 1

{9x -[4x -x +y -5y]+y} 
{9x -[3x -4y]+y} 
{9x -3x +4y+y} 
6x +5y 

Answer 2

$\{9x-[4x-(x-y)-5y]+y\}\to \\\\ \{9x-[4x-x+y-5y]+y\}\to \\\\ \{9x-[3x-4y]+y\}\to \\\\ \{9x-3x+4y+y\}\to \\\\ \boxed{\boxed{6x+5y}}$