1)2x+5(x-2)² 2)a²-x²+4x-4
1)2x+5(x-2)²=2x+5(x²-4x+4)=2x+5x²-20x+20=5x²-18x+20 2)a²-x²+4x-4=a²-(x²-4x+4)=a²-(x-2)²=(a+x-2)(a-x+2)