Answer: The graph is shown in the attached image below
-2x means -2*x or "-2 times x" where x is a placeholder for any number you want.
To graph y = -2x, you just need two points. Each point is of the form (x,y)
Let's plug in zero as it is often the easiest to work with.
If x = 0, then -2*x = -2*0 = 0. Notice how I replaced x with 0 and simplified.
Therefore, if x = 0, then y = 0. We have (x,y) = (0,0) as one point on this line. I have marked it as point A in the graph.
Point B is (1, -2) and it is found by plugging x = 1 into the equation to get...
y = -2x
y = -2*1
y = -2
You could find other points, but two points is enough to draw a straight line through them. The slope of this line is -2 = -2/1. The y intercept is 0.