SOLUTION: how do i solve -3x=2y in order to graph?

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Question 72755: how do i solve -3x=2y in order to graph?
Found 3 solutions by jim_thompson5910, rmromero, bucky:
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
-3x=2yStart with given equation
%28-3x%29%2F2=cross%282%2F2%29yDivide both sides by 2 to isolate y
y=%28-3%2F2%29xNow you can graph.

Answer by rmromero(383) About Me  (Show Source):
You can put this solution on YOUR website!


how do i solve -3x=2y in order to graph?



    You can write your equation as slope-intercept form of the equation

                  

                  y = mx + b

                -3x = 2y       divide both sides by 2.

                -3x 

                ___ = y , m = -3/2 and b = 0

                 2   



To graph:

Remember that y-intercept have point at (0,y)

 since b=0, the y-intercept have a point at (0,0).



Using the y-intercept and slope, we can find the other point



from (0,0) we move three unit down since the numerator of the slope is -3

and move two units right since the denominator of the slope is 2.

So the other point is located at (2, -3)



Let us see the graph



    graph+%28200%2C+200%2C+-3%2C4%2C+-5%2C+4%2C+%28-3%2F2%29x%29

Answer by bucky(2189) About Me  (Show Source):
You can put this solution on YOUR website!
You don't really need to do anything different to get this graph. All you need to have is two
points to establish the graph. You can get these points by choosing convenient or easy to work
with values for x and then calculating the corresponding values for y.
.
For example:
.
You are given the equation -3x=2y. Suppose we let x = 0. The equation becomes:
-3%2A%280%29+=+2%2Ay which reduces to 0+=+2y and dividing both sides by 2 results in:
0+=+y. So we have one point on the graph: x = 0 and y = 0 or (0,0).
.
Choose another value for x: let x = +4. Substituting that value into the original equation
results in +-3%2A4+=+2y+ which after the multiplication on the left side becomes
-12+=+2y. Then dividing both sides by 2 tells us that -6+=+y. So the point
(+4, -6) is also on the graph. Plot these two points on the graph and draw a line through
them. That is the graph.
.
Note that it is always a good idea to work out a third point to see if it also falls on
the graph. If it does, then you are probably correct in your graph. But if it does not
line up, then one of your points is incorrect.
.
When you are done your graph should look like this one:
.
graph%28500%2C500%2C-20%2C20%2C-20%2C20%2C+%283%2F2%29%2Ax%29
.
Hope this method saves you some work and helps you to gain some insight into graphing
techniques.