equations have got me stuck?

Question

Graph the equations by first solving for Y


2x-3y=12

How do I do this backwards and still come up with the correct answer????

Please show me how you do this. Thank you

Answer 1

2x-3y = 12

2x = 12+3y
x = (12+3y) /2
x = 6 +3y/2
plotting this graph you need to assume value for y:

begin with y =0
substitute to get value of x:

x = 6 + 3(0)/2
x = 6
that means your first point at y = 0 is (6,0)

in your x and y axis mark the value for y=0 and x = 6
then use y = 1 you get x = 7.5 your second point will be (7.5,1), and so on until you come up with graph..


Check the following websites on graphing:
http://www.homeworkhelp.com/homeworkhelp/freemember/text/math/high/algebra1/ch05/02/main.htm
http://www.math.com/school/subject2/lessons/S2U4L3GL.html

Answer 2

In order to solve the equation for y, isolate the term -3y by subtracting 2x from both sides yielding

-3y = 12 - 2x

now divide both side of the equation by -3 in order to isolate the y variable yielding

y = -4 + 2/3x

if we just re-arrange the terms on the right we get

y = 2/3x - 4

which is in slope-intercept form y = mx + b

so the y-intercept is (0, -4) and the slope of the line is 2/3. To graph this line, just plot the y-intercept and go up 2 units and to the right 3 units and plot another point here, at (3, -2). Connect the two points and you have your line graphed.

When you solve it "backwards" I assume you mean you are solving the equation for the x variable. You will still get the same graph as long as you did all your arithmetic correct because we can represent the graph of the line with an equations using the x as the independent variable and the y as the dependent, or the y as the independent and the x as the dependent.

The equation 2x - 3y = 12 is a well-defined relationship between the x-coordinate and the y-coordinate of a certain set of points (the line) in the x-y plane.

Answer 3

You don't do it backwards; follow instructions.

Solving for y you get y = [-2x + 12] / (-3) which
becomes y = (2/3) x - 4

That last equation indicates a straight line with y intercept of
- 4, and a slope of 2/3.

Locate (0, - 4) -- the y intercept as one point; then from there move horizontally a positive 3 units, then vertically a positive 2 units for your second point. Then draw your line thru those 2 points. (The exact size of THESE 3 units and 2 units isn't as critical as the need for the 3 units to be 1&ahalf as big as the 2 units.)

Answer 4

3y = 2x - 12
y = (2/3) x - 4
To graph the equation, require two points on the line:-
(0 , - 4) and (6 , 0) would be two such points.
Line may now be drawn.
Additional point may be used as a check
e.g.(12 , 4) should also lie on line that passes thro` (0 , - 4) and (6 , 0)

Answer 5

-3y = 12 - 2x
y = (12 -2x) / -3
y = (2x - 12) / 3

to plot the graph... substitute different values of x into the equation from 0 and you will get the value for y....

then make a table and write it down and finally plot it.

hope it helps!! :-)