1. If x 2+4Y 2-2x+4Y+2 = 0, then x+y = _ _ _

2. Given that X+Y+Z = A and XY+YZ+ZX = B, the value of X 2+Y 2+Z 2 is _ _ _

3. If 4x 2-mxy+9y 2 is a completely planar mode, then m = _ _ _ _

4. _ _ _ _ and _ _ of congruent graphs

Answer the question:

1.(a+b)(a-b)+(b^2-a^2)(a+b)(a-b)

2. Given that x 3+x 2+x = 0, find the value of x 2003+x 2002+x 2001-2000.

3. Given that (ax+b) (x+2) = 2 (x+ 1) 2-(x+4), find A+2B.

4. Given X+2Y=0, find the value of x 3+2xy (x+y)+4y 3.

This is a bit difficult.