Respuesta :

wegnerkolmp2741o

Answer:

y = -5

Step-by-step explanation:

-3x +9y = -57

Let x = 4

-3*4 +9y = -57

-12 +9y = -57

Add 12 to each side

-12+12 +9y = -57+12

9y = -45

Divide each side by 9

9y/9 = -45/9

y = -5