I have a system with components A, B, and C. The system operates if components A and C or B and C operate. I need to find the probability that the system will be operating. I have the probabilities that a machine will operate, but am not sure how to enter them into an equation.

So far, I'm looking at this equation as a possibility:

p(A)*p(C)+p(B)*p(C)-p(A)*p(B)*p(C)