x+3y=9

Solve for y

y=3?

No.

What happened to the x?

y=1/3x+3?

isn't the x term negative?

y= -1/3x+3?

To solve for y in the given equation x + 3y = 9, you need to isolate the variable y on one side of the equation. Here's how you can do it:

Step 1: Start with the equation x + 3y = 9.

Step 2: Subtract x from both sides of the equation to move the x term to the other side:
x + 3y - x = 9 - x
This simplifies to:
3y = 9 - x

Step 3: Divide both sides of the equation by 3 to isolate the y term:
(3y) / 3 = (9 - x) / 3
This simplifies to:
y = (9 - x) / 3

Now, the equation is solved for y in terms of x. So, y = (9 - x) / 3.

However, you mentioned that y = 3. To check if this is a valid solution, substitute y = 3 into the original equation:

x + 3y = 9
x + 3(3) = 9
x + 9 = 9
x + 9 - 9 = 9 - 9
x = 0

So, when y = 3 and x = 0, the equation x + 3y = 9 is satisfied. Therefore, y = 3 is a valid solution to the equation.