haven't run across one with three terms. help? preferably explain how you got the answer too!!

Answer:
c^3 + c^2 - 7c + 20
Step-by-step explanation:
First, expand the expression using distributive property.
c^2(c+4) - 3c(c+4) + 5(c+4)
c^3 + 4c^2 - 3c^2 - 12c + 5c + 20
Lastly, simplify like terms.
c^3 + c^2 - 7c + 20