Question

What is x+2y=6 2x-4y=-12

Answer 1

x + 2y = 6
2x - 4y = -12
Multiply the first equation by - 2
-2x - 4y = -12

This is the same as the second equation

So there are infinite solutions to these 2 equations

Answer 2

X+2y=6
2y=6-x .............(i)
now
2x-4y=-12
x-2y=-6
x-6+x=-6
2x=0
X=0
y=6