Question 37158
We take the value for y in the second equation

y = 2x – 4   and plug it in to the first equation

8x – 4y = 16   to get

8x - 4(2x – 4) = 16.  Simplifying, we get

8x - 8x + 16 = 16  and 16 = 16.  Since this is always true, for any value of x, we know that this is a dependent system with an infinite number of solutions.