Question

X + 2y =13

X - y =4
Sistema de equação

Answer 1

x- y= 4 ou seja x- 4 = y
x+2y =13

x + 2(x-4) = 13
x+ 2x -8 = 13
3x = 13+8
x= 21
      3
x = 7

7- 4 = y
y = 3

Answer 2

1) x + 2y = 13                    2) x - y = 4                RESULTADO FINAL : (7;3)
                                                   
1) x = 13 - 2y                     2) 13 - 2y - y = 4       ESPERO TER AJUDADO.

1) x = 13 - 2 . 3                  2) -3y = 4 -13

1) x = 13 - 6                       2) -3y = -9

1) x = 7                              2) -y = - 9/3

                                          2) -y = -3

                                          2) y = 3