Respuesta :

Answer:

(3x-2)(5x+2)

Step-by-step explanation:

we have to multiply 15 and 4.

then find the factors of this product.

we get,

15 x 4=60

Now, factors of 60 which make 4 are 6 and 10

because   6-10=-4

So,

[tex]15 x^{2}-4x-4\\ =15x^{2} -10x+6x-4\\[/tex]

Now, we have to take common factor pairwise.

Taking 5x as common factor from first pair and 2 from second pair,

we get

[tex]15x^{2} -10x+6x-4\\=5x(3x-2)+2(3x-2)\\=(3x-2)(5x+2)[/tex]

(3x - 2 )(5x + 2 )

consider the factors of the product 15 × - 4 = - 60

which sum to give the coefficient of the middle term ( - 4 )

the factors required are - 10 and + 6

split the x- term using these factors

15x² - 10x + 6x - 4 ( factor by grouping )

= 5x(3x - 2) + 2(3x - 2)

Take out the common factor (3x - 2)

= (3x - 2)(5x + 2)