(x-y)2
(a+b)(a-b)
(80-30)2
5x-18=8+3x
(4x2-2xy+5)-(x2+xy-1)
2ab2; -5a2b; -3ab2; 4ab2 y a2b.
2500
3ab2+3a2b
x=13
3x2-3xy+6
x2-2xy+y2
a2-b2
