1. The way to graph this with plotting points is that you choose random values for x and you can find out what your y value becomes.
2. For example let's pick 1, 3, and 5 for our x values.
If you plug in those x values into the function y=−2x, you get:
y=−2(1) so your y equals −2.
Therefore your point on the graph is (1,−2).
y=−2(3) which equals −6.
So another point on the graph is (3,−6).
y=−2(5) and that will give you −10.
So there you have another point on your graph which is (5,−10).
You can carry on plugging in different values for x and see what your y becomes.
3. Finally you can plot and connect all the points on the graph and you will get a straight line. If that will pass through the point (0,0), and has a slope of −2 which means whichever point you pick on the line you just drew, your graph goes down 2 and right 1, down 2 right 1, down 2 right 1, and so on.
Here is the graph:
graph{-2x [-10, 10, -5, 5]}
Hope this helped (c:
