Question

me ajudemm, por favor​

Answer 1

Resposta:

x = 3

y = 4

Explicação passo-a-passo:

$\left \{ {3x +3y=21} \atop {3x-y=5}}(.3) \right.\\\\\left \{ {3x +3y=21} \atop {9x-3y=15}} \right.+\\\\12x= 36\\x =\frac{36}{12} \\x = 3\\\\3x-y = 5\\-y = 5 -9\\-y=-4\\y=4$