SOLUTION: Using AX=BY+C solve and graph: x-2y=4

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Question 170159: Using AX=BY+C
solve and graph:
x-2y=4
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!

x-2y=4 Start with the given equation.


-2y=4-x Subtract x from both sides.


-2y=-x%2B4 Rearrange the terms.


y=%28-x%2B4%29%2F%28-2%29 Divide both sides by -2 to isolate y.


y=%28%28-1%29%2F%28-2%29%29x%2B%284%29%2F%28-2%29 Break up the fraction.


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


Looking at y=%281%2F2%29x-2 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 up 1 and over 2



So starting at , go up 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-2

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