There isn't any choices given in this problem but I can give you a tip to answer these kinds of problem. When you say independent, it means that the equation cannot be algebraically altered to result to 3x + 4y = 8. So the equation 6x + 8y = 16 is not an independent equation since when you divide each side by 2 it will result to 3x + 4y =8. You get the idea.