Question

x + 3y = 22
-2x + y = -23

Answer 1

Resposta:

x + 3y = 22

-2x + y = -23

$x = 22 - 3y \\ \\ - 2 \times (22 - 3y) + y = - 23 \\ - 44 + 6y + y + 23 = 0 \\ - 21 + 7y = 0 \\ 7y = 21 \div 7 \\ y = 3 \\ \\ x = 22 - 3 \times 3 \\ x = 22 - 9 \\ x = 13$

(x,y) = (13,3)