Respuesta :

choixongdong
rewrite (1st) equation
-x -  2y = - 9
multiply the (1st) equation by 3 
-3x - 6y = -27

now you have
-3x - 6y = -27
 3x - 6y = -15
-----------------------add
-12y = -42
     y = 3.5

2(3.5) = -x + 9
7 = - x + 9
x = 2

answer
(2 ,  3.5)