Solve 2x - 2y = 8 for y

Step by step

The question

Question: solve for y in 2x − 2y = 8.

We treat the other letters like numbers.

1 Remove the 2x

We want y by itself.

The 2x is in the way.

To remove 2x, we take away 2x.

We do it on both sides.

They make zero.

Cross them out.

Now we have −2y = 8 − 2x.

2 Remove the −2

−2y means −2 times y.

We want just y.

To remove times −2, we divide by −2.

We do it on both sides.

−2 divided by −2 is 1.

So just y is left.

Now we have y = (8 − 2x) over −2.

3 Make it simpler

We can make it simpler: we divide each part by −2.

So y = x − 4.

4 Check

Let's check with numbers.

We pick x = 5.

Our answer gives y = 1.

Now we put all the numbers into the start.

First the left side.

Now the right side.

Both sides are 8.

So our answer is right!

Let's look back.

First: remove the 2x.

Then: remove the −2.

Then: make it simpler.

Last: check.