(y-4)(y+4)
(b-9)(b+9)
(b+3)(b²-3b+9)
(3m+4)²= (3m+4)(3m+4)
(5x+4+3x-2)*(5x+4-3x+2)= (8x+2)(2x+6)= 2(4x+1)*2(x+3)= 4(4x+1)(x+3)
(y-4)(y+4)
(b-9)(b+9)
(b+3)(b²-3b+9)
(3m+4)²= (3m+4)(3m+4)
(5x+4+3x-2)*(5x+4-3x+2)= (8x+2)(2x+6)= 2(4x+1)*2(x+3)= 4(4x+1)(x+3)