Expand and simplify the following: -3(2x-1)^2 + 12x^2

Can someone please show me their working of this so I can get my head around it!

Hope that this is helpful.

Step-by-step explanation:

-3(2x-1)^2+12x^2

= -3[(2x-1)(2x-1)]+12x^2

=-3[2x(2x-1)-1(2x-1)]+12x^2

=-3(4x^2-2x-2x+1)+12x^2

=-3(4x^2-4x+1)+12x^2

=-12x^2+12x-3+12x^2

=(-12x^2+12x^2) +12x-3

=0+12x-3

=12x-3

the answer will be