Given,

7x² – 19x – 6

Now, first we have to find out the numbers whose-

Sum = - 19 and

Product = 7 × - 6 = - 42

The numbers are 21 and 2,

So,

7x² – 19x – 6

= 7x² – 21x + 2x – 6

= 7x(x – 3) + 2(x – 3)

= (x – 3)(7x + 2)