Respuesta :

S1NGH

Answer:

6

Step-by-step explanation:

→ Set up 2 simultaneous equations

2x + y = 12

3 + x = y

→ Substitute 2nd equation into 1st

2x + 3 + x = 12

→ Simplify and solve

3x = 9 ⇔ x = 3

→ Substitute back

x = 3, y= 6