SOLUTION: graph -2x-4y=-8

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Question 225055: graph -2x-4y=-8
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
-2x-4y=-8 Start with the given equation.


-4y=-8%2B2x Add 2x to both sides.


-4y=2x-8 Rearrange the terms.


y=%282x-8%29%2F%28-4%29 Divide both sides by -4 to isolate y.


y=%28%282%29%2F%28-4%29%29x%2B%28-8%29%2F%28-4%29 Break up the fraction.


y=-%281%2F2%29x%2B2 Reduce.




Looking at y=-%281%2F2%29x%2B2 we can see that the equation is in slope-intercept form y=mx%2Bb where the slope is m=-1%2F2 and the y-intercept is b=2


Since b=2 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 -1%2F2, this means:

rise%2Frun=-1%2F2


which shows us that the rise is -1 and the run is 2. This means that to go from point to point, we can go down 1 and over 2



So starting at , go down 1 unit


and to the right 2 units to get to the next point



Now draw a line through these points to graph y=-%281%2F2%29x%2B2

So this is the graph of y=-%281%2F2%29x%2B2 through the points and