2a^2+5a=-3
2a^2+5a+3=0
(2a+3)(a+1)=0
2a+3=0或者a+1=0
2a+3=0
2a=-3
a(1)=-1.5
a+1=0
a(2)=-1
a(1)=3/2=-1.5或者a(2)=-1
答:a(1)=-1.5 a(2)=-1
2a^2+5a=-3
2a^2+5a+3=0
(2a+3)(a+1)=0
2a+3=0或者a+1=0
2a+3=0
2a=-3
a(1)=-1.5
a+1=0
a(2)=-1
a(1)=3/2=-1.5或者a(2)=-1
答:a(1)=-1.5 a(2)=-1