一元二次方程是初中数学学习的重点.本文给出一元二次方程的两个性质,并举例说明其应用,供同学们学习参考.一、性质性质1:在一元二次方程ax2+bx+c=0 (a≠0)中,若a+b+c=0,则x1=1,x2=ca. 证明:由a+b+c=0,得b=-a-c.将其代入原方程,得ax2+(-a-c)x+c=0,即(x-1)(ax-c)=0.因 The quadratic equation of one element is the focus of mathematics learning in junior middle school. This paper gives two properties of the quadratic equation of one yuan, and gives an example to illustrate its application, for students to learn reference. First, the nature of the property 1: one-dimensional quadratic equation ax2+bx+ In c=0 (a≠0), if a+b+c=0, then x1=1, x2=ca. Proof: From a+b+c=0, get b=-ac. Substituting it into the original equation , get ax2+ (-ac) x + c = 0, that is (x-1) (ax-c) = 0.