How do you graph y=-2x by plotting points?

1 Answer
Dec 23, 2016

See Explanation

Explanation:

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: