Question 292187
1.{{{12x-6y=-15}}}
2.{{{-4x+2y=5}}}
Multiply eq. 2 by 3 and add to eq. 1 to eliminate x.
{{{12x-6y-12x+6y=-15+15}}}
{{{0=0}}}
Eq. 1 and eq. 2 are the same line. 
Multiply eq. 2 by (-3) to get eq. 1.
Consistent dependent system of equations, infinitely many solutions.