Relax

Respuesta :

6x + y = x + 5y
5x = 4y 

4x + 6x + y = 180
10x + y = 180 so y = 180 - 10x 

substitute y = 180 - 10x  into 5x = 4y
5x = 4y
5x = 4(180 - 10x )
5x = 720 - 40x
45x = 720
    x = 16

answer A.
x = 16