(1)5x+3+x的平方=0
(x+5/2)²=-3+25/4=13/4
x+5/2=±√13/2
x=(-5±√13)/2
(2)(x-1)的平方-5(x-1)+6=0
(x-1-2)(x-1-3)=0
(x-3)(x-4)=0
x=3或x=4