Question

How to graph -x + 2y = 6

Answer 1

In order to graph the equation, you need some coordinates, 
So, put x = 0, 
2y = 6. y = 3.  Coordinate = (0, 3)

Now, put y = 0, 
-x = 6
x = -6   Coordinate (-6, 0)

In short, Just mark that two points and draw a line, graph is done

Hope this helps!