Answer:
k = P - m - n
Explanation:
The question is asking you to rearrange the equation so that k is alone on one side.
P = k + m + n
P - k = (k + m + n) - k
P - k = m + n
(P - k) - P = m + n - P
-k = m + n - P
-1(-k) = -1 (m + n - P)
k = -m - n + P
The equation is completely simplified so this is your answer.