SOLUTION: 3x-y=9 Graph the function, Briefly explain how you graphed the function.

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Question 661646: 3x-y=9
Graph the function, Briefly explain how you graphed the function.
Found 2 solutions by MathLover1, josmiceli:
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

3x-y=9
3x-9=y
it's linear function, graph will e a line; so, all you need is the (x,y) coordinates of two points, plot them on Cartesian coordinate system and draw a line through
so, choose two values for variable;easiest way is to find x-intercept and y-intercept
set x=0 and find y-intercept
3%2A0-9=y
-9=y
one point is (0,-9)

set y=0 and find x-intercept
3x-9=0
3x=9
x=3

second point is(3,0)

now graph it:
+graph%28+600%2C+600%2C+-10%2C+10%2C+-10%2C+10%2C+3x-9%29+

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
+3x+-+y+=+9+
Add y to both sides
+3x+=+9+%2B+y+
Subtract 9 from both sides
+3x+-+9+=+y+
Write it the other way around
+y+=+3x+-+9+
1st make +x+=+0+
+y+=+3%2A0+-+9+
+y+=+-9+
(0,-9) is the 1st point
-------------------
Make +y+=+0+
+0+=+3x+-+9+
+3x+=+9+
+x+=+3+
(3,0) is the 2nd point
------------------
Here's the plot
+graph%28+400%2C+400%2C+-5%2C+10%2C+-12%2C+5%2C++3x+-+9+%29+