SOLUTION: how do you graph the equation -3x-y=6 ?

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Question 342045: how do you graph the equation -3x-y=6 ?
Found 2 solutions by jim_thompson5910, Alan3354:
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
-3x-y=6 Start with the given equation.


-y=6--3x Add 3x to both sides.


-y=--3x%2B6 Rearrange the terms.


y=%28--3x%2B6%29%2F%28-1%29 Divide both sides by -1 to isolate y.


y=%28%28--3%29%2F%28-1%29%29x%2B%286%29%2F%28-1%29 Break up the fraction.


y=-3x-6 Reduce.


Looking at y=-3x-6 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=-6


Since b=-6 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-6

So this is the graph of y=-3x-6 through the points and


If you need more help, email me at jim_thompson5910@hotmail.com

Also, feel free to check out my tutoring website

Jim

Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
It's a straight line, so you need 2 points.
Pick 2 values of x and find y.
Plot the 2 points.
Draw a line thru them.
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