help please

Question

Factor the following polynomials completely:

 

A) 3x^4-12x^2

 

B) 4x^2-12x+9

 

C) 6x^2-x-12

 

D) 3x^3+3x^2y-18xy^2

Answer 1

A)

 

To factor, we take out the greatest common factor (GCF).  The GCF is 3x².

 

3x²(x² - 4)

 

 

One of these factors is a difference in perfect squares.

 

3x²(x - 2)(x + 2)

 

 

B)

 

We factor this using the FOIL method.

 

(2x - 3)(2x - 3)

 

 

C)

 

Factor using FOIL method.

 

(3x + 4)(2x - 3)

 

 

D)

 

Take out the GCF.  GCF is 3x.

 

3x(x² + xy - 6y²)

 

 

The larger factor can be factored using FOIL.

 

3x(x + 3y)(x - 2y)