How do you graph the equation y=-3x+2?

1 Answer

See below:

Explanation:

This equation is in slope-intercept form, which is my favourite for graphing lines.

The slope-intercept form is in the general form of:

y=mx+b

where m is the slope and b is the y-intercept.

Let's graph the y-intercept first.

The y-intercept is 2. This means that that point is (0,2). So let's graph that:

graph{(x-0)^2+(y-2)^2-.3^2=0}

So that's one point. Now let's plot another point (and then we can use a straightedge to join them).

The slope is -3. Slope is calculated by "rise"/"run" - in other words the change in y divided by the change in x. In this case, we will drop 3 spots for every 1 spot we move right. So that point is (0+1, 2-3)=(1,-1). Let's graph that:

graph{((x-0)^2+(y-2)^2-.3^2)((x-1)^2+(y+1)^2-.3^2)=0}

And now connect them up!

graph{((x-0)^2+(y-2)^2-.3^2)((x-1)^2+(y+1)^2-.3^2)(y+3x-2)=0}