How do you factor by grouping #28s^2 - 37s - 21#?
1 Answer
Factoring
There are 2 methods.
1. Factoring AC method (factoring by grouping) .
Find 2 numbers b1 and b2 that satisfy these 2 conditions:
Sum:
and
Product:
To find
Proceed:
We find
( since their sum is
Next factor by grouping:
Factored form:
f(x) = (4x - 7)(7x + 3)
2. The new AC method to factor a trinomial f(x)
First convert trinomial (1) to
trinomial:
with
Compose factor pairs of
and apply the Rule of Sign for Real Roots.
Proceed:
This sum is
Then
Next, divide
to get
and
Then, the factored form is:
This new AC Method avoids the lengthy factoring by grouping.