SOLUTION: Graph the equation 2x + y = 9

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Question 149956: Graph the equation
2x + y = 9

Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
2x+%2B+y+=+9 Start with the given equation.


y=9-2x Subtract 2x from both sides.


y=-2x%2B9 Rearrange the terms.




Looking at y=-2x%2B9 we can see that the equation is in slope-intercept form y=mx%2Bb where the slope is m=-2 and the y-intercept is b=9


Since b=9 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 -2, this means:

rise%2Frun=-2%2F1


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



So starting at , go down 2 units


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



Now draw a line through these points to graph y=-2x%2B9

So this is the graph of y=-2x%2B9 through the points and