第1个回答 2011-09-19
1.x^2+3x+2=0. 2.x^2+5x+4=0 3.x^2+9x+8=0 4.x^2+6x+8=0 5.x^2+20x+64=0
6.x^2-3x+2=0 7.x^2-7x+10=0 8.x^2+3x-4=0 9.x^2-3x-10=0 10.x^2-x-56=0
11.2x^2+5x+2=0 12.4x^2+24x+27=0 13.12x^2-13x+3=0 14.28y²-25y+3=0
15.2x^2-5-12=0 16 3x^2-5x-2=0 1 7. 6x^2-13x+5=0 18.7x^2-19x-6=0
19.x^2+(根号3+根号2)x+根号6=0 20.(根号2)x^2-(1+根号2)x+1=0