First solve for y?

Question

I need help on this hard to pick up on it
2x-3y=12 I do not understand how to get to Y=-2/3+4 so that I can plot it

OK how do I plot it I guess I have to do it three times in this class! So do I replace X or Y with 0 or do I use 0 for both?

I really thank everyone in your efforts in guiding me to the answer!

Answer 1

2x-3y=12 subtract 2x from each side
-3y=12-2x divide both sides by -3
y=2x/3-4

Answer 2

Hey...follow the rules...
equation 2x - 3y = 12.....Divide by 3
becomes 2/3 x - y = 4.....subtract 4 and add y to both sides
becomes 2/3 x + 4 = y
Substitute values for x to get y and plot.

Answer 3

2x - 3y = 12

-3y = 12 - 2x (subtract 2x from both sides OR add -2x to both sides)

next, you will divide both sides by -3 to get:

y = (12 - 2x) / -3

you can re-write this as:

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


reduce (12 / -3) and simplify - (2 / -3) and get:

y = 4 + (2 / 3)x

also written as :

y = - (2x / -3) + 4

in order to plot this keep in mind the standard form (as opposed to the point-slope form):

y = mx + b

in the final equation, the slope (m) is (2/3) and the y-intercept (b) is 4.

plotting the equation:

using the equation y = (2/3)x + 4, plug in any number for x, and get the corresponding value for y. for example:

take x = 3, plug it into the eqn. and get:

y = (2/3)(3) + 4
y = 2 + 4
y = 6

so your coordinates are (3,6). you can do this for any x value and get the corresponding y value.

Answer 4

2x - 3y = 12 ...............(1)
Multiply by -1:
-2x + 3y = -12
Divide by 3:
-2x/3 + y = -4
Add 2x / 3 to each side:
y = 2x / 3 - 4.

I don't understand how to get that result either. It's wrong.

This is a straight line graph. To plot it, put x = 0, giving:
y = -4.
Then put y = 0 in (1), giving:
2x = 12
x = 6.
Draw the line through the two points (6,0) and (0,-4).

Answer 5

alright.. first things first..

when solving an equation, it means you are trying to have the y variable all by itself..

but in algebra we are only allowed to either add, subtract, multiplied and divide,.. question is, which do we do first?..

its quite simple really..

lets take an easier example first..
say, we have y + 8 = 9

here, since we need the y to be all alone on one side, we need to remove the 8, out of there, legally..
which means, either addition or subraction?..

that's right, subtraction, since the 8 is a positive value, we add the opposite, which is a -8.. anothe way of saying
subtract 8 from both sides, equally....

remeber, what ever you do to one side, we do to the other..

hence, y+8-8= 9-8
so that we get y= 1..

now, applying that concept to our equation

2x-3y=12,,

we need to remove the 2x,

that's right, subtract 2x from both sides...

to get -3y = 12 -2x

and now, since the -3 is multiplied by the y, we do that opposite again, and divide both sides by -3 equally... that's right.. every thing gets divided by -3.. and we end up with

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

to finally get
y= -4 + (2/3) x

or if we change it around a bit..
y= (2/3) x -4

Answer 6

2x-3y=12 I
3y=2x-121
y=2x/3-121/3

Answer 7

x=11

Answer 8

2x = 12 + 3y
2x - 12 = 3y
3y = 2x - 12
y = (2/3).x - 4

Answer 9

first subtract 2x from both sides

then divide both sides by -3
this will give you the solution you are looking for