I need to know how to factor by grouping and how to factor completely in Algebra 2

Factoring is a big topic - too big to address adequately in this short space. Try looking over this lesson on factoring.

If you have specific questions, or would like a specific equation factored, post it here and we'll help.

---------

126x

^{3}-54x^{2}-210x+90Group as follows:

(126x

^{3}-54x^{2}) - (210x-90)You can factor an 18x

^{2}out of the terms in the first parentheses and a 30 out of the terms in the second parentheses:18x

^{2}(7x-3) - 30(7x-3)Now factor out the (7x-3):

(18x

^{2}-30)(7x-3)Finally, I can factor out a 6 from the terms in the first parentheses:

**6(3x**

^{2}-5)(7x-3)Check by multiplying out the factored expression (FOIL) to verify that you get the original expression back.

## Comments

^{3}-54x^{2}-210x+90^{3}-54x^{2}) - (210x-90)^{2}out of (126x^{3}-54x^{2})^{3}-54x^{2}) = 18x^{2}(7x-3)^{2}(7x-3) - 30(7x-3)^{2}(7x-3) - 30(7x-3) = (18x^{2}-30)(7x-3)6(3x^{2}-5)(7x-3)