3x-2y=18 solve for x

Question

I am confused by ' for x '

Answer 1

The issue most student have is that the answer to this is not a number, it is an expression.  The question want you to isolate the variable x on the left side to the equal sign.

 

 

Step 1: add 2y to both sides

 

 

   Result:  3x = 18 + 2y     OR    3x = 2y +18  depending on what your teacher likes

 

Step 2: divide each term by 3

 

   Result : 3/3 x = 18/3 + 2/3 y

 

Step 3: simply fractions if needed

 

   Result: x = 6 + 2/3 y   this is the answer

 

Answer 2

Hi Briana, 

 

You are simply trying to isolate X (ie solve for x). By having X on one side of the equation, you are solving for it. In this case:

 

3x - 2y = 18

3x = 18 + 2y

x = 18/3 + 2/3y

x = 6 + 2/3y