x²+3a²=4ax-2a+1 (m+n)x²+2nx=m-n(m+n≠0) a²

x²+3a²=4ax-2a+1,
x^2-4ax+3a^2+2a-1=0,
x^2-4ax+(3a-1)(a+1)=0,
(x-3a+1)(x-a-1)=0,
x1=3a-1,x2=a+1
(m+n)x²+2nx=m-n
(m+n)x^2+2nx+n-m=0,
[(m+n)x+(n-m)](x+1)=0,
x1=(m-n)/(m+n),x2=-1
a²（x²-x+1)-a(x²-1)=(a²-1)x
a^2x^2-a^2x+a^2-ax^2+a-(a^2-1)x=0,
(a^2-a)x^2-(2a^2-1)x+a^2+a=0
[(a-1)x-a][ax-(a+1)]=0,
x1=a/(a-1),x2=(a+1)/a