A. Always because imagine a line where one is y=x and the other is y=-x+1. The point of intersection would be (1,1)
Answer:
(x-y)(x-y)(x-y)= x²-yx+x²-yx-yx+y²-yx+y²
2x²-4yx+2y²
(y-x)(y-x)= y²-yx-yx+x²
y²-2yx+x²
-(y²-2yx+x²) = -y²+2yx-x²
2x²-4yx+2y²-y²+2yx-x²= x²-2yx+y²
or
(x−y−1)(x−y)² ≡ x³−x²+3xy²+2xy−y³−y²−3yx³
99 is more than 100 when you add 2 to 99. xD