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Question 988382: plot the points.
f(x) = -3/5x + 28/5
For the rise and run plot, I got (-5,8) but the book had (-4,8). I don't think my answer is wrong because I counted off from 5 at the y-axis 3 units up, and run 5 units to the left which gave me (-5,8). Is the answer from the book a typo or am I wrong?
Found 2 solutions by Boreal, solver91311:
Answer by Boreal(15235)   (Show Source):
You can put this solution on YOUR website! f(x)=-3x/5+28/5
if y=8,
8 =the above.
multiply everything by 5
40=-3x+28
-3x=12
x=-4
When x goes to the left 4, y goes up (0.6) since the slope is -3/5. Four units of x=2.4 units of y, and that takes the graph from (0,5.6) to (-4,8). The point that you know immediately is (0,28/5). That is where you count from.
Answer by solver91311(24713)  (Show Source):
You can put this solution on YOUR website!
You say you started at the point (0,5). Why did you start there? The  -intercept is ) , which is to say )
The point (-5,8) is NOT on your line. You know that because \ =\ -\frac{3}{5}(-5)\ +\ \frac{28}{5}\ \not{=}\ 8) . I'll leave it to you to verify the arithmetic.
On the other hand, (-4,8) IS on the line. Again, I'll leave the arithmetic to you.
Rather than start at the intercept, the person who came up with the textbook solution began at the nearest point to the -intercept that had integer coordinates, specifically the point (1,5). I think if you go up 3, left 5 from that point you will find yourself at (-4,8).
John
My calculator said it, I believe it, that settles it
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