-2(18-3y)=7y+2y; How do you solve the problem when there are 3 variables?

Answer 1

There aren't really 3 variables, since y is the only letter used, there is only 1 variable. You just have to combine and isolate the variable to one side.

First, multiply -2 by 18 and -3y each. This gives you one side of the equation.

Then, combine 7y and 2y on the other side of the equation.

You should now have a y on each side. To isolate the variable, do the inverse (opposite) operation. If one side is 2 + y, then you would subtract y from each side (because to keep an equation balanced, you must do the same thing to each side).

You should now have a number that = some y's. Since 7y (for example) actually means 7 * y, we also do the inverse here to find the value of one y. So you divide each side by the number of y's you have to find the value of one y.

I hope this helps. I'm sure you'd rather I just told you the answer!

Answer 2

2x-3y+5z = -9 .......I x+2y-3z = 2 .........II 3x-z = -8 .............III Multiply the 1st equation via 2 and the 2nd equation via 3 and upload those 2 new equations 4x-6y+10z = - 18 3x+6y-9z = 6 after addition we get 7x+z = -12 ........IV Now upload the third and the fourth equations, we get 10x = - 20 x = -20 / 10 = -2 replace the cost of x interior the third equation we get 3* ( - 2 ) - z = - 8 - 6 - z = - 8 - z = - 8 + 6 = - 2 z = 2 replace the values of x and z interior the 1st equation we get 2* (-2) - 3y + 5*2 = - 9 - 4 - 3y + 10 = - 9 - 3y = - 9 + 4 - 10 - 3y = - 15 y = - 15 / - 3 = 5 consequently the values of x = - 2, y = 5 and z = 2

Answer 3

You only have one variable....y.....and it appears 3 times in your equation.

First, get rid of the parentheses
(-2) * 18 - (-2) * 3y = 7y + 2y
-36 + 6y = 9y

Than you take all terms that contain y to one side and all the others to the other side (do not forget to change the signs when you take one term from one side to the other):
-36 = 9y -6y
-36 = 3y
y = -36/ 3
y = -12

Answer 4

first think you need to do is simplify the equation by combining like variables, so the equation would look like:
-2(18-3y) = 9y

Then get rid of the parentesis by doing the multiplication:
-36 + 6y = 9y

Simplify the equation again, so the variable is on one side, and numeric values are on the other.
-36 = 3y

then, solve the equation by dividing both sides so you end up with = . In this case, we divide by 3...and y = -12

you can use the same steps for any problem where you have multiple instances of the same variable... hope this helps some!

Answer 5

There is really only one variable "y". Your job is to put like terms together through the rules of mathematics. Whenever you see a number next to some terms in parentheses, it means you have to multiply it by both of the terms:

-2(18-3y) = 7y + 2y

-2 * 18 = -36 and -2 * -3y = + 6y, so we get:

-36 + 6y = 7y +2y

Now you want to get the y's on one side of the equal sign and the numbers on the other and whatever you do on one side of the equal sign you have to do to the other.

First let's subtract 6y from both sides:

-36 = 7y-6y+2y


Now let's simplify:

-36 = 3y

Now divide both sides by 3:

-12 = y

Answer 6

First you do:
-2 times 18 which is36
and then -2 times -3y which is -6y
You rewrite your the problem
36-6y=7y+2y
And you add 7y and 2y together which give you
7y+2y=9y
36-6y=9y
You take away the six to the nine
9y-6y=3y
now you can solve the problem
36=3y
36 divided by 3=12
y=12


I hope I'm right i tried my best for you. you might want to verified it.

Answer 7

first, simplify to -36 + 6y = 7y + 2y
then transpose, -36 = 7y + 2y - 6y
-36 = 3y
-36 / 3 = y
-12 = y

Answer 8

When the variable is "y" three different times you can add or subtract them....

first distribute the two: -36 + 6y = 7y + 2y

now you can add or subtract the "y's": -36 = 3y

and y is equal to -12

Answer 9

-2 (18 - 3y) = 7y + 2y
-36 + 6y= 9y
-36 = 9y - 6y
-36 = 3y
-36 / 3 = y
y = -12

Answer 10

y is the only variable you have!

-2(18-3y)=7y+2y
36+6y=9y
36=3y
y=12

Get some extra help, math is a lot of fun when taught the right way....pretend you are a detective solving a crime!