x2 + 2x - 15
= x2 - 3x + 5x - 15
= x(x - 3) + 5(x - 3)
= (x + 5)(x - 3)
X2 + 4xx(x + 4)=======
x2 + 6x = x*(x + 6)
x(x+5)
4(x2 + 4)
(x+5)(x+3)
(x-7)(x-3)
(x + 11)(x - 4)
x2 + 4x = x(x + 4)
(x-5)(x+11)
1(x2-1)
X3 + 8= (x+2)(x2-2x+4)
x3+xy-x2y2=x(x2+y-xy2)