+73 to expand this polynomial, we should multiply the factors in order from left to right. hopefully you can follow this process -
5w + 5*4 + w^2 + 4w.
to simplify, we combine the like terms, to get:
w^2 + 9w + 20
hope this helped! sorry if this wasn't too clear.
here are a few websites that may help you understand this better:
https://www.brainfuse.com/jsp/alc/resource.jsp?s=gre&c=35257&cc=108827#:~:text=A%20polynomial%20is%20expanded%20if%20no%20variable%20appears,3x(4%20-%20x)%20%2B%20(2x%20-%205)%202
also try out Symbolab's expansion calculator. it provides a step-by-step expansion of polynomial expressions as well.
if you have some time, give these a try! Google searches are also useful to help you learn more too! 
