The given expression is
[tex]4d+12e[/tex]The greatest common factor is 4 because both terms can be divide by 4 at the same time.
[tex]\frac{4d}{4}+\frac{12e}{4}=d+3e[/tex]Then, we factor out the greatest common factor to express it in factor form
[tex]4(d+3e)[/tex]