To get from here

to here

We do this:

First multiply the matrices together:

Now set the two matrices equal to each other:

We can write the matrices as a system of equations:

Thus, if we set each equation equal to zero, we have

Now, how do we determine and ?

There are infinitely many solutions.

I'll pick a simple one: and

These two values, and any integer multiple of them will satisfy the equation we came up with.

Does this make sense?

--Chris