SOLUTION: Graph using the slope and y-intercept. -3x - y = 0

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Question 237438: Graph using the slope and y-intercept.
-3x - y = 0

Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
-3x-y=0 Start with the given equation.


-y=3x Add 3x to both sides.


-y=3x Rearrange the terms.


y=3x%2F%28-1%29 Divide both sides by -1 to isolate y.


y=-3x Reduce.




Looking at y=-3x we can see that the equation is in slope-intercept form y=mx%2Bb where the slope is m=-3 and the y-intercept is b=0 note: y=-3x really looks like y=-3x%2B0


Since b=0 this tells us that the y-intercept is .Remember the y-intercept is the point where the graph intersects with the y-axis

So we have one point




Now since the slope is comprised of the "rise" over the "run" this means
slope=rise%2Frun

Also, because the slope is -3, this means:

rise%2Frun=-3%2F1


which shows us that the rise is -3 and the run is 1. This means that to go from point to point, we can go down 3 and over 1



So starting at , go down 3 units


and to the right 1 unit to get to the next point



Now draw a line through these points to graph y=-3x

So this is the graph of y=-3x through the points and