SOLUTION: Graph 3x-4y=8 using the slope and y-intercept

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Question 134833: Graph 3x-4y=8 using the slope and y-intercept
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!

3x-4y=8 Start with the given equation


-4y=8-3x Subtract 3+x from both sides


-4y=-3x%2B8 Rearrange the equation


y=%28-3x%2B8%29%2F%28-4%29 Divide both sides by -4


y=%28-3%2F-4%29x%2B%288%29%2F%28-4%29 Break up the fraction


y=%283%2F4%29x-2 Reduce




Looking at y=%283%2F4%29x-2 we can see that the equation is in slope-intercept form y=mx%2Bb where the slope is m=3%2F4 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 3%2F4, this means:

rise%2Frun=3%2F4


which shows us that the rise is 3 and the run is 4. This means that to go from point to point, we can go up 3 and over 4



So starting at , go up 3 units


and to the right 4 units to get to the next point



Now draw a line through these points to graph y=%283%2F4%29x-2

So this is the graph of y=%283%2F4%29x-2 through the points and