I have an equation in form of (a+b)*c =d, where "a" and "c" are unknown quantities.

Example, assigning b=4 and d=188, the equation now becomes:

(a+4)*c=188

1) Is it possible to derive the value of "a" by any means ?

2) What is the contribution of 4 in the answer 188 in relation with "a"

3) Does this gives rise to probability values for "a". If yes, is there any constant for this probability ?

Thanks in advance.

Please reply

mahesh