1) (x+5)(x+1)-x(x+2)=20-x 2)(x-1)(x-4)-(x+2)(x+3)=4-2x 3)(x-3)(x-2)-(x+1)(2x-3)=1-x² 4)(x+5)²-2(x+1)(x-2)+(x+3)(x-3)=55-3x 5)(3x-1)²+(x-2)(2x+3)=(3x+2)(3x-2)+2(x-2)²-15 6)(x-rd5)²-(x+rd5)²=rd20 7) (4x+3)²-(x-1)(x-3)=(4x+1)(4x-1)-(x+5)(x-2)+2(15x+2) 8)(x+rd3)(x-rd3)_(x-rd3)²=12 9) rd7x-3rd7=9-x 10) (x+rd2)(x-rd2)-(x-rd2)²=(x+rd2)²-x²-x