Question

resposta do sistema {2x + 5y=13
{-2x + 7x=23

Answer 1

2x + 5y = 13

-2x + 7y = 23

12y= 36

y= 36/12

y= 3                        

 2x + 5 (3) = 13

2x +15 = 13

2x= 13-15

2x= -2

x= -2/2

x= -1