How do you factor #3x^2 - 12#?

1 Answer
Jan 2, 2016

3(x-2)(x+2)

Explanation:

when factorising follow these steps
(1) is there a common factor?
(2) is it a trinomial ?
(3) is it a difference of 2 squares ?

in this case there is a common factor of 3 (1)

#3x^2 - 12 = 3(x^2 -4)#
inside the bracket is a difference of 2 squares (3)
#x^2 -4 = (x-2)(x+2)#
so #3x^2 - 12 = 3(x-2)(x+2)#