This is a school assignment...so I am not looking for anyone to do it for me...but I need some help on the way to get started with this one...

Here we go....

I have a matrix A:

1, 1, 1-t
1, 0, t
t+1, 1, 1

and a matrix B:
4, 1, 1
3, 1, 1
5, 1, 1

and a matrix X that is 3*3. When t = 2 we have that

AX = B + X

What is the X matrix....???

We have just started with matrixes so I ain't any good, so I am not sure what I am allowed to do with them. Can I move any of them to the other side? Or where can I start??? Any help are appreciated...