16y2 - 4x2 - 12x - 9 = 16y2 - (4x2 + 12x + 9) = 16y2 - (2x + 3)2 = (4y - 2x - 3)(4y + 2x + 3)
\(16y^2-4x^2-12x-9=16y^2-\left(4x^2+12x+9\right)=\left(4y\right)^2-\left(2x+3\right)^2=\left[4y-\left(2x+3\right)\right]\left[4y+\left(2x+3\right)\right]\)
=16y2 - (4y2 + 12x + 9)
=(4y2 )-(2y + 3)2
=(4y-2y-3)(4y+2y+3)
mik nha