Question

Solve 3x+5y=30 for y

Answer 1

`y=(-3)/(5)x+6`

Explanation:

3x+5y=30 is the given equation.

We are asked to isolate y.

The term that contains y is 5y. I'm going to first isolate 5y.

To isolate 5y we see that we have +3x with it. To undo addition of 3x we will need to subtract 3x on both sides.

3x+5y=30

-3x -3x

5y=-3x+30

We now have 5y by itself. There is actually one step left to get the y by itself.

The last step is undo this multiplication between 5 and y.

To undo multiplication you divide.

So we will be dividing 5 on both sides. This gives us:

3x+5y=30

-3x -3x

5y=-3x+30

-- ---------

5 5

So the whole reason we did that is because 5y/5 is just y. I'm going to separate that fraction on the right hand side. This gives me:

y=-3/5 x + 30/5

I'm going to simplify the 30/5 to 6.

y=-3/5 x +6

Answer 2

y =
`(30-3x)/(5)`

Explanation:

Given

3x + 5y = 30

Isolate the term in y by subtracting 3x from both sides

5y = 30 - 3x ( divide both sides by 5 )

y =
`(30-3x)/(5)`