Can someone please explain this to me and answer it? I fan and medal :)

Choose the equivalent system of linear equations that will produce the same solution as the one given below.

6x + 2y = -6
3x - 4y = -18

•12x + 4y = -12
15x = -30
• 8x + 4y = -4
14x = -10
• 6x - 8y = -36
-6y = -42
• 6x - y = -15
3y = 9

Question

Can someone please explain this to me and answer it? I fan and medal :) 

Choose the equivalent system of linear equations that will produce the same solution as the one given below.

6x + 2y = -6
3x - 4y = -18

•12x + 4y = -12
15x = -30
• 8x + 4y = -4
14x = -10
• 6x - 8y = -36
-6y = -42
• 6x - y = -15
3y = 9

radar · Answer

Take the first equation (6x +2y = -6) and multiply all terms by 2.
combine with the 2nd equation (3x - 4y = -18) eliminate y.

Now look at the options, don't you see it???