Verified answer

3P -(P-1)

Distributive property: 3P - P + 1

Combine: 2P + 1

And that is the simplest form.

(edit: it is + 1 because when you are using the distributive property pretend that the problem is 3P -1(P-1) you multiply the whole problem by -1 resulting in -1*P= -P and -1*-1= +1)

(edit2: not the whole problem just what is in the parenthesis)

3p-(p-1) = 3p - p + 1 = 2p + 1

hope that help