4xx-8x+1=16(9xx+12x+4)
4xx-8x+1=144xx+192x+64
140xx+200x+63=0
△=40000-4*140*63=4720
根号△=68.7
x1=(-200+68.7)/280=-0.4689
x2=(-200-68.7)/280=-0.9596
4xx-8x+1=16(9xx+12x+4)
4xx-8x+1=144xx+192x+64
140xx+200x+63=0
△=40000-4*140*63=4720
根号△=68.7
x1=(-200+68.7)/280=-0.4689
x2=(-200-68.7)/280=-0.9596