You were told under your first post that " there is NO SOLUTION" to your problem as it is written.
If you meant to write nP2 =56, then there is a solution. If this is what you meant, then the solution in this case of "P2" is: you take the square root of 56 and round it UP to a whole integer. So, the sqrt(56) =7.4833....=8, so that 8P2=8 x 7 = 56. You can do it in a more complicated algebraic way, but is not necessary here.
