Respuesta :

Answer:

b = -4

Step-by-step explanation:

given, 3y + 12 = 6x ..........make y the subject

y = ( 6x - 12 ) / 3  ______eq 1

also given,

2y = 4x + b ........make y the subject

y = ( 4x + b )/ 2

using simultaneous equation:

( 4x + b )/ 2 = ( 6x - 12 ) / 3

12x + 3b = 12x - 24 ........x gets cancel out

3b = -24

b = -8