Changing the subject of a formula

[chuckienz]

Ok, this most likely will be a silly question but I am having trouble trying to make X the subject of the formula XA +BA = B

im hoping someone is able to enlighten me

Thanks

 

[matt grime]

What are X, A and B? It matters as it tells you what rules of manipulation are valid.

You can certainly subtract BA from both sides:

XA = B-BA

Now you need to 'divide' by A. If this is about real numbers, X=(B-BA)/A.

(If it were matrices then assuming A is invertible, X=(B-BA)A^-1.)