Expand and simplify the expression $4e+4$
This is one of the most important, critical techniques. You need to spend some time on the simpler elements of it before going on to look at quadratic factorising.
Factorising algebraic expressions is conceptually identical to numerical factorising. In both situations we are looking for things which divide exactly by something else.
So $4$ is a factor of $16$ and $p+1$ is a factor of $(p+1)^3$.