Question

ajuda plz ========================================================================================================================================

Answer 1

$\left \{ {{x+y=30} \atop {4x+2y=80}} \right. \\\left \{ {{x+y=30 (-2) } \atop {4x+2y=80 (1)}} \right.\\\left \{ {{-2x-2y=-60} \atop {4x+2y=80}} \right.\\ 2x=20\\x=10\\\\ x+y=30\\10+y=30\\y=30-10\\y=20$  

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