Simultaneous equations Isaac physics q

QUESTION:
A system is described by the following three equations:
aB=cd
MF-a=Mx
x=Bd
Express x in the form x= F/A
where A is a function of c , B and M in its simplest form.
I rearranged third equation to get d=x/B
Then put that into first equation so aB=cx/B so a=cx/B^2
Then I put this into the second equation so: MF-cx/B^2 so MF=x(M-c/B^2) which gives x=MF/M-c/B^2 which gives x=MB^2F/MB^2-c which is wrong.
Please help.

Not checked, but you need just F on the numerator, so divide both numerator and denominator by MB^2 and you get ...

MB^2 is not a factor of the denominator so I don’t think you can do that. Correct me if I’m wrong.

The desired expression on the denominator depends on M and B so
(MB^2 - c) / (MB^2) = ...
If you backed up your working a line where you had
MF = x(...)
then divide through by M to get
F = x (...)
then divide through by (...) to get
x = F/(...)

So now I did:
MF = x(M-C/B^2)
F = x(1-C/MB^2)
So x =F/(1-C/MB^2)
But this is still incorrect

Have you the isaac link / did you put
1 - c / (MB^2)
Edit - looks like you have a sign wrong when you take a term over