Respuesta :

Answer:

x = - 13

Step-by-step explanation:

2x — by = 40

y = 6x – 1

put y value in equation

2x — by = 40

2x - (6x -1) = 40

2x - 6x +1 = 40

-3x = 39

x=- 39/3

x = - 13