Factor the expression y2+6y-16

(Y+8)(Y-2)

Factoring by grouping is splitting middle terms into two appropriate terms. 
let us see the resulting expression below as we factor the expression -8x3-2x2-12x-3.

-8x3-2x2-12x-3
= 2x^2 ( -4x-1) 3 (-4x-1)
=(2x^2+3) (-4x-1)

the resulting expression after factoring -8x3-2x2-12x-3 by grouping is: 
(2x^2+3) (-4x-1)

The method factoring by grouping is widely used by college professors, teachers, students and even textbook authors.

That’d be 9 years or something