Solution - Simplification or other simple results

Step  1  :

Equation at the end of step  1  :

  ((3•7y2) -  50y) -  16

Step  2  :

Trying to factor by splitting the middle term

 2.1     Factoring  21y²-50y-16 

The first term is,  21y²  its coefficient is  21 .
The middle term is,  -50y  its coefficient is  -50 .
The last term, "the constant", is  -16 

Step-1 : Multiply the coefficient of the first term by the constant   21 • -16 = -336 

Step-2 : Find two factors of  -336  whose sum equals the coefficient of the middle term, which is   -50 .

Step-3 : Rewrite the polynomial splitting the middle term using the two factors found in step 2 above,  -56  and  6 
                     21y² - 56y + 6y - 16

Step-4 : Add up the first 2 terms, pulling out like factors :
                    7y • (3y-8)
              Add up the last 2 terms, pulling out common factors :
                    2 • (3y-8)
Step-5 : Add up the four terms of step 4 :
                    (7y+2)  •  (3y-8)
             Which is the desired factorization

Final result :

  (3y - 8) • (7y + 2)