400(1+x)+(1+x)²=1324
400+400x+x²+2x+1-1324=0
x²+402x-923=0
x=(-402±√(165296))/2
=-201±√41324(x²+y²)²-(x²+y²)-12=(x²+y²)²-(x²+y²)-12=x=?，y=？(x²+y²)²-(x²+y²)-12=(x²+y²+3)(x²+y²-4)