A.fff\(x^2+3x+3=0\)/fff
B.fff\(x^2+8x+15=0\)/fff
C.fff\(x^2+7x+10=0\)/fff
D.fff\(x^2+10x+16=0\)/fff
E.fff\(x^2+7x+12=0\)/fff
我的答案: