how u slove a factor by grouping

Question

3y³-2y²-21y+14

 

Answer 1

What we want is to factor the first two, then the 2nd two terms and get the same thing after we factor.

 

3y² - 2y² = y²(3y - 2) 

 

-21y + 14 = -7(3y - 2)

 

Well, look at that. Both have 3y - 2. We combine what's in front in their own parentheses.

 

3y² - 2y² - 21y + 14 = (y² - 7)(3y - 2)

 

Hope this helps!