if statements with both and and or options

The problem i have is as follows

if a1 = 1 and b1 = x c1 = 5
if a1 =1 and b1 = " " c1 =0
if a1 = " " b1 1 = " " c1 = " "
if a1= " " and b1 =x error

I have not been able to develop the logic to make this work.
Any help would b appricated.

Hello, there are several ways to do this. Most importantly, not all the options are covered in the four statements above, for example what if A1=2?

=IF(A1=1,IF(B1="x",5,IF(B1=" ",0,"other")),IF(A1=" ",IF(B1=" "," ",IF(B1="x","error","other"))))

Or, if A1 can only be 1 or " " and B1 can only be " " or x, then this is shorter:

=IF(A1=1,IF(B1="x",5,0),IF(B1=" "," ","error"))

cheers,