[tex]3 {d}^{2} + 23d + 14[/tex]
first multiply 14•3 = 42
find 2 numbers that when multiplied it equals to 42 and when added it equals to 23, in this case the numbers are 21 & 2
replace the 23d with the 2 numbers
[tex]3 {d}^{2} + 21d + 2d + 14[/tex]
factor out 3d from the expression
[tex]3d(d + 7) + 2d + 14[/tex]
then factor out 2 from the expression
[tex]3d(d + 7) + 2(d + 7)[/tex]
factor out (d+7)
[tex](3d + 2)(d + 7)[/tex]
