You are only allowed one question per post. The process to be followed to factor 20w^2 + 100 w + 40 has been described.
20w^2 + 100w + 40
remove any common numeric multiples
=> 20(w^2 + 5w + 2)
w^2 + 5w + 2 cannot be factored into terms with integral roots as the roots of w^2 + 5w + 2= 0 are complex.
The factorized form of 20w^2 + 100w + 40 = 20(w^2 + 5w + 2)