a) - (-25x²+17x-21)-33x²-17x+31)= b)-38x²+5x-14-(+16x²-3x+16)=
C)114x²+33x+54+(-14x²-37x+14)= D) - (121x²+54x-19)-(17x²-37x+14)= E)-225+148-75x48xy-(75xy+18)=​