SOLUTION: -5x+4y=20

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Question 142202: -5x+4y=20
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
Do you want to graph this?


-5x%2B4y=20 Start with the given equation


4y=20%2B5x Add 5+x to both sides


4y=%2B5x%2B20 Rearrange the equation


y=%28%2B5x%2B20%29%2F%284%29 Divide both sides by 4


y=%28%2B5%2F4%29x%2B%2820%29%2F%284%29 Break up the fraction


y=%285%2F4%29x%2B5 Reduce




Looking at y=%285%2F4%29x%2B5 we can see that the equation is in slope-intercept form y=mx%2Bb where the slope is m=5%2F4 and the y-intercept is b=5


Since b=5 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 5%2F4, this means:

rise%2Frun=5%2F4


which shows us that the rise is 5 and the run is 4. This means that to go from point to point, we can go up 5 and over 4



So starting at , go up 5 units


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



Now draw a line through these points to graph y=%285%2F4%29x%2B5

So this is the graph of y=%285%2F4%29x%2B5 through the points and