(2x+1)²+(3x-2)²-13x(x-1)
(4x²+4x+1)+(9x²-12x+4)-13x²+13x
4x²+4x+1+9x²-12x+4-13x²+13x
5x+5
5(x+1)
(7x+2)²-(5x-3)²-2x(7x+29)
(49x²+28x+4)-(25x²-30x+9)-14x²-58x
49x²+28x+4-25x²+30x-9-14x²-58x
10x²-5
5(2x²-1)
